A helium burst is a very brief exergonic nuclear fusion of enormous quantities of helium into carbon using the triple-alpha mechanism that occurs inside the core of low mass stars (between 0.8 and 2.0 M).
What on the HR diagram is a helium flash?The helium flash Helium fusion starts when the helium-rich core at the RGB's tip ignites. The star moves quickly to the Horizontal Branches region of the H-R diagram as a result of the core's ignition.
Describe the helium flash. How does it affect a fading star?Helium flash refers to the sudden commencement of helium fission in a low-mass star's core. The star then stabilises and momentarily shrinks in size and brilliance. Fusion comes to an end when the core's supply of helium is depleted in planets with masses of up to twice that of the Moon or less.
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an object with a net charge of 4.80 x 10^-6 coulomb experiences an electrostatic force having a magnitude of 6.00 x 10^-2 newton when placed near a negatively charged metal sphere. what is the electric field strength at this location?
When placed near a negatively charged metal sphere.The electric field strength at this location is 1.25 × 10⁴ N/C directed toward the sphere .
Equating :Electric field strength = 6.00 ×10⁻² N - 4 .80 × 10⁶ C
= 1.25 × 10⁴N/C
Electric field strength :
The intensity of an electric field at a specific location is quantified by its electric field strength. The volt per meter (V/m or Vm-1) is the most common measurement. A potential difference of one V between two points separated by one meter is represented by a field strength of one V/m. The intensity of an electric field at a specific location is quantified by its electric field strength.
Why is there a strong electric field?Where electric field lines are closer together, the field is stronger, and where they are further apart, the field is weaker. As you get further away from a point charge, the electric field gets weaker.
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at a location in usa, it is necessary to supply 300 kw of 50-hz power. the only power source available operates at 60-hz. it is decided to generate the power by means of motor-generator set consisting of synchronous motor driving a synchronous generator. how many poles should each of the two machines have in order to convert 60-hz to 50-hz power?
The synchronous motor and generator need to have a speed ratio of 1.2 (60 Hz/50 Hz) in order to convert 60 Hz to 50 Hz power. Therefore, the number of poles in each machine must be such that their synchronous speeds are in the ratio of 1.2. So if the synchronous speed of the motor is Ns1, the synchronous speed of the generator must be Ns2 = 1.2 Ns1.
The synchronous speed of a machine is given by the formula: Ns = (120f)/P where f is the frequency and P is the number of poles.
For the motor, we get: Ns1 = (120*60)/P1
For the generator, we get: Ns2 = (120*50)/P2
Equating these, we get: P2 = 1.2 P1
So if the motor has P1 poles, the generator should have P2 = 1.2 P1 poles in order to convert 60 Hz to 50 Hz power.
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A 0. 15 kg baseball has a momentum of 0. 78 kg*m/s just before it lands on the ground. What was the ball's speed just before landing?
The ball was moving at 5.2 m/s before something dropped (also known as its velocity because it has a course of action in a given time).
Considering the data provided,
The baseball weighs 0.15 kg in terms of bulk.
A baseball has a momentum of 0.78 kilogram per second.
The momentum of an item is often exactly related to its mass and speed for something like an object travelling in such a given direction during a given period of time.
∴ Mass times speed is how you calculate momentum.
mass/momentum formula for calculating velocity
speed = 0.78 kgm/s 0.15 kg
speed = 5.2 m/s
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who was the scientist that discovered a magnetic field could be created by passing an electric current through a wire?
The scientist who discovered that a magnetic field could be created by passing an electric current through a wire was Hans Christian Oersted, a physicist and chemist.
Hans Christian Oersted's discovery was a significant breakthrough in the field of electromagnetism. In 1820, he conducted an experiment in which he observed that a magnetic needle was deflected when placed near a wire carrying an electric current. This discovery paved the way for the development of electromagnetism, which is the basis for many important technologies, including electric motors, generators, and transformers.
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a full water tank in the shape of a hemispherical bowl of radius 5 m. 5 m. how much work is required to pump all the water to a height of 5 m 5 m above the tank?
A full water tank in the shape of a hemispherical bowl of radius 5 m. 5 m. 8.6875 × [tex]10^5[/tex] J work is required to pump all the water to a height of 5 m 5 m above the tank
The amount of work required to pump all the water in the full water tank of the shape of a hemispherical bowl of radius 5m to a height of 5m above the tank is 8.6875 x [tex]10^5[/tex] J.
Let us begin by finding the volume of the hemispherical bowl of radius 5 m.
V = (2/3)πr³
where r is the radius of the hemispherical bowl.
Substituting r = 5 m in the above formula for volume,
we get
V = (2/3) × π × 5³ m³ = 523.6 m³
Since the bowl is full of water, the volume of water it contains is also 523.6 m³.
To find the mass of the water in the bowl, we need to multiply the volume by the density of water at room temperature, which is 1000 kg/m³.
Mass of water in the bowl = 523.6 × 1000 kg = 523600 kg
The potential energy of the water when it is lifted to a height of 5m above the tank is given by
mgh
where m is the mass of water, g is the acceleration due to gravity and h is the height of the water above the tank.
Substituting the given values, we get
Potential energy of water = 523600 × 9.81 × 5 J = 25690800 J
Therefore, the amount of work required to pump all the water to a height of 5m above the tank is equal to the potential energy of the water, which is 25690800 J, rounded off to 8.6875 × 10^5 J.
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the quality factor of a parallel resonance band-pass filter is found to be 0.05. if the same resistor, capacitor, and inductor are used to construct a series resonance band-pass filter, what is the quality factor of the filter?
The quality factor of a series resonance band-pass filter when the same resistor, capacitor, and inductor are used is 20.
The quality factor of a series resonance band-pass filter when the same resistor, capacitor, and inductor are used is the reciprocal of the quality factor of the parallel resonance band-pass filter.
In this case, the quality factor of a parallel resonance band-pass filter is found to be 0.05. If the same resistor, capacitor, and inductor are used to construct a series resonance band-pass filter, the quality factor of the filter is given by;
Qs = 1/QR
Where, Qs = Quality factor of a series resonance band-pass filter, QR = Quality factor of a parallel resonance band-pass filter.
Therefore,
Qs = 1/0.05 = 20
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why do you suppose that the human auditory system evolved sensitivity to sounds in the range of 20 to 20000 hz instead of some other range of frequencies?
The human auditory system evolved to be sensitive to sounds in the range of 20 to 20000 Hz because it encompasses frequencies relevant to communication and survival, and matches the resonant properties of the human ear.
The human auditory system evolved to be sensitive to sounds in the range of 20 to 20000 Hz because this range encompasses the frequencies that are most relevant for communication and survival in the natural environment. Frequencies below 20 Hz, such as those produced by earthquakes or very low-frequency sounds in the ocean, are not very useful for communication and survival in most terrestrial environments. Frequencies above 20000 Hz, on the other hand, are less important for communication in many species and also require more energy to produce and detect. The range of 20 to 20000 Hz is also well-matched to the resonant properties of the human ear, which amplifies sounds in this range. Therefore, the sensitivity of the human auditory system to this range of frequencies is likely a product of both the ecological demands and the physical properties of the ear.
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Does the claims made by Alfred Wegner (of continental drift) make sense? Explain
Wegener's theory of continental drift was an important early step in our understanding of how the continents move, but it lacked a complete explanation for the forces driving their movement.
Alfred Wegener's theory of continental drift proposed that the continents were once joined together as a single landmass, which he called Pangaea, and that they gradually moved apart over time. He suggested that the continents moved due to the forces of tides, centrifugal forces, and other factors. Although Wegener's theory was met with skepticism when it was first proposed in the early 20th century, it is now widely accepted as a valid explanation for the movement of continents.
Wegener based his theory on several lines of evidence, including the fit of the continents, the distribution of rocks and fossils, and the presence of glacial deposits in areas that are now too warm for glaciers. However, his explanation for the forces driving the movement of the continents was incomplete and lacked a plausible mechanism. It was not until the discovery of plate tectonics in the mid-20th century that a more complete explanation for continental drift was provided.
Plate tectonics explains the movement of the continents by the movement of the plates that make up the Earth's crust. The plates are driven by convection currents in the mantle, which move material up from the hot interior of the Earth, causing the plates to move apart, slide past each other, or collide. As the plates move, they carry the continents with them, causing them to drift apart or come together.
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Indeed, Alfred Wegener's assertions make logical. His hypothesis of continental drift, which is backed by a variety of geological and paleontological data, postulated that the continents were originally united together in a single landmass before drifting apart.
According to Alfred Wegener's hypothesis of continental drift, Pangaea, all the continents previously belonged to a single supercontinent. He thought the continents drifted to their present locations over millions of years after the supercontinent started to disintegrate some 200 million years ago. The matching of geological characteristics and fossils across continents, the resemblance of rock formations and mountain ranges, and the discovery of magnetic stripes on the ocean floor have all been used to support this idea, which was previously viewed with suspicion. In light of this, Wegener's assertions that the continents were originally linked and then drifted apart make sense, and his hypothesis has completely changed how we think about the Earth's past and current dynamics.
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fiber optic cable is thicker and heavier than unshielded twisted pair. question 10 options: true false
False, Fiber optic cable is thinner and lighter than unshielded twisted pair (UTP) cable.
Fiber optic cables are made up of strands of glass or plastic fibers that transmit data through light pulses. They are immune to electromagnetic interference and can transmit signals over longer distances than UTP cables, which are made up of copper wires.The content loaded Fiber optic cable is used in high-speed internet connections because it can transmit large amounts of data at very high speeds. Additionally, fiber optic cables are more secure than UTP cables because they are much more difficult to tap into without being detected. Therefore, the statement that fiber optic cable is thicker and heavier than UTP cable is false.
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a spring attached to the ceiling is stretched 100 mm when a mass of 2 kg is hung on its end. how much work must be done to compress the spring by 6 cm?
The work that must be done to compress the spring by 6 cm is 0.3528 J.
To determine the work that must be done to compress the spring by 6 cm:
[tex]U = (1/2)kx^{2}[/tex]
where U is the potential energy, k is the spring constant, and x is the displacement from the equilibrium position :
[tex]F = kx[/tex]
where F is the force exerted by the spring and x is the displacement from the equilibrium position:
[tex]F = mg = 2 kg * 9.8 m/s^{2} = 19.6 N[/tex]
[tex]k = F/x = 19.6 N / 0.1 m = 196 N/m[/tex]
Now, to find the work required to compress the spring by 6 cm (or 0.06 m), we can use the potential energy formula :
[tex]U = (1/2)kx^2 = (1/2)(196 N/m)(-0.06 m)^{2} = 0.3528 J[/tex]
Therefore, the work that must be done to compress the spring by 6 cm is 0.3528 J.
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a ski starts from rest and slides down a 30o incline 150m long. a) if the coefficient of friction is 0.15, what is the ski's speed at the base of the incline? b) if the snow is level at the foot of the incline and has the same coefficient of friction, how far will the ski travel along the level? use energy methods.
a) Using energy methods and assuming negligible air resistance, the speed of the ski at the base of the incline is approximately 34.1 m/s. b) The ski will travel approximately 110.6 m along the level snow.
a) When the ski descends the gradient, its original potential energy is transformed into kinetic energy. Friction causes part of this energy to be wasted, which reduces the ski's speed at the bottom of the hill. The ski's ultimate kinetic energy may be calculated by subtracting the work done by friction from its starting potential energy using the laws of energy conservation. b) The ski only has kinetic energy left as it reaches the bottom of the gradient since all of its potential energy has been expelled. The ski's kinetic energy is transformed into thermal energy as it travels down the flat snow by the frictional force pressing on it, slowing it down until it ultimately comes to a stop. making use of energy saving once more.
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12. If a person fires a gun, specifically at the head, will the person feel any pain the second the bullet hits? Explain.
Answer:
No.
Explanation:
It will be soo painful that the person won't be able to feel it any,ore the person will feel nothing but dieing and can't talk
Q10:
A room contains a book, a chair, a bookshelf, and a hatch that leads to a basement, as show in the diagram. The book has a weight of 7.5 N The seat of the chair is 0.45 m above the floor of the room, the bookshelf is 1.5 m above the floor of the room, and the basement floor is 2.2 m below the floor of the room. The book is placed in various positions and its gravitational potential energy changes depending on its position.
A)How much can the gravitational potential energy of the book decrease if the book is released from a point on the floor of the room, to the left of the hatch?
B)How much can the gravitational potential energy of the book decrease if the book is released from a point on the floor of the room, to the right of the hatch?
C)How much can the gravitational potential energy of the book decrease if the book is released from a point at the height of the chair seat?
D)How much can the gravitational potential energy of the book decrease if the book is released from a point at the height of the bookshelf?
Answer:
To calculate the change in gravitational potential energy of the book as it falls from different starting points, we need to use the formula:
ΔPE = mgh
where ΔPE is the change in gravitational potential energy, m is the mass of the book, g is the gravitational acceleration (9.81 m/s^2), and h is the change in height.
A) If the book is released from a point on the floor of the room to the left of the hatch, it will fall towards the hatch and then fall further towards the basement floor. The change in height is the distance from the floor to the basement floor, which is 2.2 meters. Therefore, the change in gravitational potential energy is:
ΔPE = (7.5 N) x (9.81 m/s^2) x (2.2 m) = 162.8 Joules
B) If the book is released from a point on the floor of the room to the right of the hatch, it will fall towards the hatch and then fall further towards the basement floor as well. Therefore, the change in gravitational potential energy is the same as in Part A:
ΔPE = (7.5 N) x (9.81 m/s^2) x (2.2 m) = 162.8 Joules
C) If the book is released from a point at the height of the chair seat (0.45 m above the floor), it will fall towards the hatch and then fall further towards the basement floor. The change in height is the distance from the chair seat to the basement floor, which is:
h = 0.45 m + 2.2 m = 2.65 m
Therefore, the change in gravitational potential energy is:
ΔPE = (7.5 N) x (9.81 m/s^2) x (2.65 m) = 187.8 Joules
D) If the book is released from a point at the height of the bookshelf (1.5 m above the floor), it will fall directly towards the basement floor. The change in height is the distance from the bookshelf to the basement floor, which is:
h = 1.5 m + 2.2 m = 3.7 m
Therefore, the change in gravitational potential energy is:
ΔPE = (7.5 N) x (9.81 m/s^2) x (3.7 m) = 268.4
a top is a toy that is made to spin on its pointed end by pulling on a string wrapped around the body of the top. the string has a length of 80 cm and is wound around the top at a spot where its radius is 2.0 cm. the thickness of the string is negligible. the top is initially at rest. someone pulls the free end of the string, thereby unwinding it and giving the top an angular acceleration of 10 rad/s2. what is the final angular velocity of the top when the string is completely unwound?
The top reaches an angular velocity of 28.28 rad/s when the string is fully unwound.
We can use the kinematic equation of rotational motion to solve this problem. The third kinematic equation relates the final angular velocity of a rotating object to its initial angular velocity, angular acceleration, and the angle through which it rotates:
[tex]\omega_f^2 = \omega_i^2 + 2\alpha\theta[/tex]
where θ is the angle through which the object rotates.
The number of turns the body turns to unwind the string is calculated as,
[tex]n=L/(2\pi r)[/tex]
[tex]n=80/(2\pi \times 2)[/tex]
[tex]n=6.366[/tex]
Therefore the angle turned by the body in unwinding the string is calculated as,
[tex]\theta = 2\pi \times 6.366 \ rad[/tex]
[tex]\theta = 39.99\ radians[/tex]
The initial angular velocity of the top is zero, the angular acceleration is [tex]10 \ rad/s^2[/tex], and we need to find the final angular velocity when the string is completely unwound.
Substituting the values given in the problem into the equation, we get:
[tex]\omega_f^2 = 0 + 2\times 10 \times 39.99[/tex]
Simplifying, we get:
[tex]\omega _f = 28.28 \ rad/s[/tex]
Therefore, the final angular velocity of the top when the string is completely unwound is 28.28 rad/s.
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When a particle is a distance r from the origin, its potential energy function is given by the equation U(r)=kr, where k is a constant and r=x2+y2+z2−−−−−−−−−−√
(a) What are the SI units of k?
Part B (b) Find a mathematical expression in terms of x, y, and z for the y component of the force on the particle.
Part C (c) If U=3. 00 J when the particle is 2. 00 m from the origin, find the numerical value of the y component of the force on this particle when it is at the point (-1. 00 m, 2. 00 m, 3. 00 m)
The SI unit of k is, the y component of the force is given by and the y component of the force on the particle is J/m,-ky/√(x² + y² + z²) and -0.429 J/m respectively.
(a) The potential energy function of a particle is given by U(r) = kr, where k is a constant. The units of k can be determined by considering the units of potential energy and distance. The SI unit of potential energy is joules (J), and the SI unit of distance is meters (m). Therefore, the SI unit of k is J/m.
(b) The force on a particle is given by the negative gradient of the potential energy function. That is,
F = - ∇U
where ∇ is the gradient operator. In Cartesian coordinates, the y component of the force is given by:
Fy = - ∂U/∂y
To find ∂U/∂y, we need to express U in terms of y. Using the equation for r given in the problem statement, we have:
r² = x² + y² + z²
Substituting this expression into the equation for U, we get:
U = kr = [tex]k(x^2 + y^2 + z^2)^{(1/2)}[/tex]
To find ∂U/∂y, we differentiate U with respect to y, treating x and z as constants:
∂U/∂y = ky/√(x² + y² + z²)
Therefore, the y component of the force is given by:
Fy = - ∂U/∂y = -ky/√(x² + y² + z²)
(c) Given that U = 3.00 J when the particle is 2.00 m from the origin, we can use the equation U = kr to find the value of k:
k = U/r = 3.00 J / 2.00 m = 1.50 J/m
To find the y component of the force on the particle at the point (-1.00 m, 2.00 m, 3.00 m), we need to calculate y and plug it into the expression we derived in part (b):
y = 2.00 m
Fy = -ky/√(x² + y² + z²) = -1.50 J/m × 2.00 m / √((-1.00 m)² + (2.00 m)² + (3.00 m)²) = -0.429 J/m
Therefore, the y component of the force on the particle is -0.429 J/m.
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Which one of the following statements concerning a convex mirror is true? Explain your choice. a) Such mirrors are always a portion of a large sphere. b) The image formed by the mirror is sometimes a real image. c) The image will be larger than one produced by a plane mirror in its place d) The image will be closer to the mirror than one produced by a plane mirror in its place e) The image will always be inverted relative to the object
Therefore, option c) is the correct statement since the image produced by a convex mirror is always smaller than the object and hence larger than one produced by a plane mirror in its place.
What is a convex mirror?A convex mirror is a spherical mirror with its reflective surface bulging outward, away from the incident light. It is also called a diverging mirror since it diverges the incoming light rays.
What type of image is formed by convex mirror?The image formed by a convex mirror is always virtual, meaning that it cannot be projected on a screen. It is formed by the apparent intersection of the reflected light rays, and it appears to be behind the mirror. Since the light rays are diverged by the convex mirror, the image produced is always smaller than the actual object. Hence, option e) is false.
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what is the likely cause of the haze seen in photographs of pluto's atmosphere taken by the new horizons spacecraft?
The likely cause of the haze seen in photographs of Pluto's atmosphere taken by the New Horizons spacecraft is the scattering of sunlight by small particles in the atmosphere.
What is haze?Haze is a phenomenon in which dust, smoke, and other dry particles obscure the clarity of the sky. It causes visibility to be reduced, which makes distant objects appear blurry, and causes the sky to appear dull and gray. The same phenomenon can occur in space as well, where it is called a space haze.
What is Pluto?Pluto is the smallest dwarf planet in the Solar System and was discovered in 1930. It is located in the Kuiper Belt, a region beyond the orbit of Neptune that contains many small icy bodies. Pluto is the largest object in the Kuiper Belt, with a diameter of 2377 km. In 2015, NASA's New Horizons spacecraft flew by Pluto and provided us with the first close-up images of the planet.
What is New Horizons?New Horizons is a NASA spacecraft that was launched in 2006 with the goal of studying Pluto and the Kuiper Belt. It flew by Pluto in 2015 and took a number of photographs of the planet and its atmosphere. The spacecraft also studied the composition of the atmosphere, the geology of the surface, and the structure of Pluto's moons.
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A car moves along a horizontal plane road where friction is two thirds of the weight of the car and the mass of the car is m Calculate the coefficient of friction If the car moves with acceleration of 2.4m/s² calculate the propelling force of the car engine
Solution calculate the fermi energy for silver assuming 6.1 ? 10 22 free electrons per cubic centimeter. (assume the effective mass equals the free electron mass.)
The fermi energy for silver, assuming the effective mass equals the free electron mass is 5.58 x 10⁻¹⁹ J.
How to calculate fermi energy?To calculate the Fermi energy for silver, use the following formula:
E_F = (h² / 2m) × (3π² × n)^(2/3)
where:
h = Planck's constant = 6.626 x 10⁻³⁴ J s
m = effective mass of electron = mass of free electron = 9.109 x 10⁻³¹ kg
n = number density of free electrons = 6.1 x 10²² electrons/cm³
Substituting the given values into the formula:
E_F = (6.626 x 10⁻³⁴ J s)² / (2 × 9.109 x 10⁻³¹ kg) × (3π² × 6.1 x 10²² cm⁻³)^(2/3)
E_F = 5.58 x 10⁻¹⁹ J
Therefore, the Fermi energy for silver is approximately 5.58 x 10⁻¹⁹ J.
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PLEASE HELP ME!
Look at the periodic table and answer these questions:
1. Which elements are in the same group?
O and Te
O and F
O and He
2. Which elements are in the same period?
O and Te
O and F
O and He
I WILL GIVE YOU 50 POINTS IF YOU GIVE ME THE RIGHT ANSWER!!
what capacitance is needed to store this much charge in a capacitor with a potential difference between its plates of 9.5
The capacitance is needed to store charge Q in a capacitor with a potential difference between its plates of 9.5 is Q/9.5
A capacitor is a two-terminal electrical device that can store energy in the form of an electric charge. It consists of two electrical conductors that are separated by a distance. The space between the conductors may be filled by vacuum or with an insulating material known as a dielectric.
Capacitance is expressed as the ratio of the electric charge on each conductor to the potential difference (i.e., voltage) between them.
The capacitance needed to store charge Q in a capacitor with a potential difference between its plates of 9.5 is given by the formula:
C= Q/V
Where, C is the capacitance, Q is the charge stored, and V is the potential difference between the plates.
Therefore,
C= Q/9.5
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an isolated conducting sphere has a 15 cm radius. one wire carries a current of 1.0000020 a into it. another wire carries a current of 1.0000000 a out of it. how long would it take for the sphere to increase in potential by 1260 v?
The increase in potential by 1260 V would take t = 1260V * (2π * 0.15)/(μ * 0.0000020) seconds.
The potential difference across a conducting sphere of radius r is given by V = (μ I)/2πr, where μ is the magnetic permeability and I is the current passing through the sphere.
In this case, the radius of the sphere is 15 cm, the current passing into the sphere is 1.0000020 A, and the current passing out of the sphere is 1.0000000 A.
Substituting the given values into the equation for potential difference, we get:
V = (μ (1.0000020 - 1.0000000)) / (2π * 0.15)
Therefore, the increase in potential by 1260 V would take t = 1260V * (2π * 0.15)/(μ * 0.0000020) seconds.
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suppose you are pushing a 4 kg box with a force of 25 n (directed parallel to the ground) over a distance of 18 m. afterward, the box (initially at rest) is traveling at a speed of 5 m/s. how much work (in joules) did friction do in this process?
In the given process, work done by the friction is equal to the work done by the force applied. The work done by the force applied is equal to the product of force and distance, i.e. 25N x 18m = 450J.
The work done by friction will be equal to the change in kinetic energy of the box which is equal to 1/2 mv², where m is the mass of the box and v is the velocity of the box. Here, m = 4kg and v = 5m/s.
Therefore, work done by friction = 1/2 x 4x (5)² = 50J. Thus, the total work done by the friction in the given process is 50J.
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What must be the mass of a chunck of aluminum that takes 8550 J of engery ti be heated from 50 C to 72 C
what optical power of eyegalss lens is needed to correct vision of a nearsighted person whose far point is 30cm
The optical power of eyeglass lens required to correct the vision of a nearsighted person with a far point of 30cm is -3.33 diopters (D).
The optical power of an eyeglass lens required to correct the vision of a nearsighted individual is determined by their far point. The far point is the maximum distance at which the person can see objects clearly without any visual aids. A nearsighted individual has a far point that is closer than the normal far point of infinity. To determine the optical power needed to correct the nearsightedness, the far point distance is converted to meters and then the reciprocal of that value is calculated to obtain the optical power in diopters. For example, if the far point is 30 cm, the optical power needed to correct the nearsightedness is approximately 3.33 diopters. This optical power can be achieved by wearing eyeglass lenses with the appropriate refractive power.
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brody the dog is sitting at your feet like a good boy. you throw a dog toy away from you at a speed of 34 m/s (good arm). brody runs after the ball at a constant speed of 7 m/s. the toy is designed to make a constant high frequency tone of 950 hz as it flies through the air. what frequency does brody hear initially as he chases the toy?
Brody initially hears the frequency of the toy as 1071 Hz (approximately).
To solve this problem, we need to use the Doppler effect formula, which relates the frequency of a wave to the relative motion between the source and the observer.
The frequency heard by Brody initially:
[tex]f' = f * (v + vo) / (v + vs)[/tex]
where f is the frequency of the toy (950 Hz), v is the speed of sound (assumed to be 343 m/s at room temperature), vo is the velocity of the observer (Brody, running at 7 m/s), and vs is the velocity of the source (the toy, moving away from Brody at 34 m/s).
[tex]f' = 950 Hz * (343 m/s + 7 m/s) / (343 m/s - 34 m/s)\\\f' = 950 Hz * 350 / 309\\\\\f' = 1071 Hz (approximately)[/tex]
Therefore, Brody initially hears the frequency of the toy as 1071 Hz (approximately).
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a sample of gas has a volume of 12L and a pressure of 1atm. if the pressure of a gas is increased to 2atm, what is the new volume of gas?
Answer:
p1v1=p2v2
v2=p1v1/p2
=(1 atm ×12 L)/2 atm
v2= 6 L
if a 1.3 v battery stores 6.7 kj of energy (a reasonable value for an inexpensive c cell), for how many minutes could it sustain a current of 1.3 a ? if a 1.3 battery stores 6.7 of energy (a reasonable value for an inexpensive c cell), for how many minutes could it sustain a current of 1.3 ? 2.3 min 6.9 min 9.4 min 66 min
The time could it sustain a current of 1.3 A is 3.96 minutes.
To calculate the time it can sustain a current of 1.3 A, we divide the Power = Voltage x Current
in the battery (in Joules) by the current (in Amps).
The voltage of the battery is 1.3 V
The energy stored in the battery is 6.7 kJ
The current drawn by the battery is 1.3 A
We know that,
Power = Voltage x Current
P = 1.3 x 1.3
P = 1.69 W
Now,
Energy = Power x Time
6.7 kJ = 1.69 W x Time
Time = 6.7 kJ/1.69 W
Time = 3.962 min ≈ 3.96 min
Hence, the battery could sustain a current of 1.3 A for about 3.96 minutes.
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in an electron microscope, what accelerating voltage is needed to produce electrons with wavelength 0.0600 nm ? (hint: the initial kinetic energy is negligible.)_______ V
Answer:
The accelerating voltage needed to produce electrons with wavelength 0.0600 nm is 590 V.
Explanation:
In an electron microscope, the accelerating voltage needed to produce electrons with wavelength 0.0600 nm is 590 V.
What is an electron microscope?An electron microscope is a microscope that employs a beam of electrons as a source of illumination. Because of their short wavelengths, electrons can provide higher resolution images than light microscopes.
Theoretically, this would make it possible to distinguish between two points that are less than a single angstrom apart (0.1 nm).
In an electron microscope, the accelerating voltage needed to produce electrons with a wavelength of 0.0600 nm is given by the de Broglie wavelength equation.
The formula for de Broglie wavelength is: λ = h / p Where,λ is the wavelength of electrons. h is Planck's constant, 6.63 × 10−34 J·s. p is the momentum of electrons, m·v.
Now, the momentum of an electron is given by: m· v = √(2mkT) Here, m is the mass of electrons, k is Boltzmann's constant, and T is the temperature.
As the initial kinetic energy is negligible, we assume that the initial velocity of electrons is zero.
Therefore, the formula for momentum becomes: m· v = √(2mkT) = √(2m·0·kT) = 0 Also, we know that p = mv So, p = 0, which means λ = h / p = ∞This indicates that the de Broglie wavelength of the electrons is undefined, or infinite.
Therefore, we cannot use the de Broglie wavelength equation to find the accelerating voltage.
However, we can use the following formula to find the accelerating voltage: voltage = (h^2 / 2m) × (1 / λ^2)Substituting the given values, we get: voltage = (6.63 × 10^-34 J·s)^2 / (2 × 9.11 × 10^-31 kg) × (1 / (0.0600 × 10^-9 m)^2)
Therefore, the accelerating voltage needed to produce electrons with wavelength 0.0600 nm is 590 V.
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The movement of crustal plates is best described as a:
1) Trend toward increased crust movement overtime
2) Series of events that happens quickly
3) continuing long-term process
4) process that has a predictable pattern
The movement of crustal plates is best described as a continuing long-term process.
Plate tectonics is a theory of geology that describes the movement and interactions of lithospheric plates that cover the Earth's surface. There are three types of plate boundaries: divergent, convergent, and transform. They all have varying rates of movement and result in various geological phenomena.
As a result, the movement of crustal plates is best described as a continuing long-term process. Crustal plates move slowly over time as they are pushed and pulled by the Earth's internal forces. The direction and speed of movement vary from one plate to another, and the rate of movement is determined by several factors, including the thickness and composition of the lithosphere.
Plate tectonics is a process that operates on a global scale and has a significant impact on the Earth's surface features and geological history.
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