The time taken by the ball to fall through a distance of 30m is, 2 seconds
To calculate the time taken to fall through a distance of 30m, we have given data as,
mass of ball = 200g
g = 10 m/s^2
Initial height = 50 meter
Final height = 30 meter
So by the laws of motion, we have,
Δh = (ut) + (at²/2)
where, (u = initial velocity), and (t = time)
So,
50-30 = (0.t) + [10 x t²)/2]
20 = 5t²
Therefore, t = ± (2 seconds)
On eliminating the negative value as time can`t be negative here, we get
t = 2 seconds
Therefore, the time taken by the ball to fall through a distance of 30m is, 2 seconds
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A simple circuit exists with two identical light bulbs. The two light bulbs are in series with one another. If one light bulb is removed, which of the following would occur?
The current would increase.
The current would decrease.
The total resistance would increase.
The total voltage would decrease.
The current would decrease if one light bulb is removed from the circuit. Option B is correct.
If one light bulb is removed from a simple circuit with two identical light bulbs that are in series with one another, the total resistance in the circuit would increase. This is because the resistance of the circuit is proportional to the number of resistors in the circuit, and removing one bulb reduces the number of resistors in the circuit.
The total current in the circuit would decrease because the resistance has increased. This is because the current flowing through a circuit is inversely proportional to the resistance of the circuit according to Ohm's law. Option B is correct.
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Two small Styrofoam balls that are separated (between their centers) by 4 cm experience a force of attraction of 15 N. If the balls are separated by 8 cm, the force between them would be ___ N.
Answer:
f = 15/4 = 3.75
Explanation:
When light is restricted to oscillating in a single plane, that is known as
diffraction
dispersion
interference
polarization
the answer is polarization.
A tourist, who weighs 705 N, is walking through the woods and crosses a small horizontal bridge. The bridge rests on two concrete supports, one at each end. He stops on the bridge. Assume that the board of the bridge has negligible weight. Where is he standing if the magnitude of the vertical force that a concrete support exerts on the bridge at the near end is 470 N?
а)one-fifth of the way along the bridge b)one-fourth of the way along the bridge c)one-third of the way along the bridge d)one-half of the way along the bridge f)one-sixth of the way along the bridge
The tourist is standing one-third of the way along the bridge (option c).
How to solveLet's denote the distance from the near end of the bridge to the point where the tourist is standing as x and the total length of the bridge as L.
According to the equilibrium condition, the sum of the forces exerted on the bridge is zero.
So, the vertical forces exerted by the two concrete supports should be equal to the weight of the tourist:
F_near + F_far = 705 N
Given that the magnitude of the vertical force exerted by the near end support is 470 N, we can calculate the force exerted by the far end support:
F_far = 705 N - 470 N = 235 N
Now, we can use the moment equilibrium condition, considering moments around the near end support:
Moment = Force × Distance
For the tourist:
Moment_tourist = 705 N × x
For the far end support:
Moment_far = 235 N × L
For equilibrium, the sum of the moments should be zero:
Moment_tourist - Moment_far = 0
Substituting the moments:
705 N × x - 235 N × L = 0
Now, we can solve for x/L, which represents the fraction of the way along the bridge where the tourist is standing:
x/L = (235 N × L) / 705 N
x/L = 235/705 = 47/141 ≈ 1/3
So, the tourist is standing one-third of the way along the bridge (option c).
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A rifle with a weight of 30 N fires a 5.0-g bullet with a speed of 300 m/s. (a) Find
the recoil speed of the rifle. (b) If a 700-N man holds the rifle firmly against his
shoulder, find the recoil speed of man and rifle.
_______________________________
Notes:
1grain = 64.8mg
1newton = 100g
= 300 m/s (speed)
= 30 × 100
= 3,000g (rifle mass)
= 5-g × 64.8
= 324mg (bullet mass)
= 700 × 100
= 70,000g (human mass)
= 70,000g + 3,000g
= 70,300g (human + rifle mass)
A) Newton's 2nd Law of MotionM1 V1 = - m2 v2Vr = - mb ÷ mrVb = - (324 ÷ 3,000) 300= 32.4 m/sB) Newton's 2nd Law of MotionM1 V1 = - m2 v2Vr = - mb ÷ mr Vb = - (324 ÷ 70,300) 300= 1.39 m/s_______________________________
1. Two resistors R₁ (12 ohm) and R₁ (24 ohm) are
connected in series across a 6.0 V battery
of negligible internal resistance.
I
Draw a circuit diagram (to the right) and calculate:
The total resistance of the two resistors:
The total current flowing in the circuit:
The current flowing in R₁
The current flowing in R2
The total power consumed by R₁ and R₂
||
S
To calculate the total resistance of the two resistors in series, we add them:
R_total = R₁ + R₂ = 12 ohm + 24 ohm = 36 ohm
To calculate the total current flowing in the circuit, we use Ohm's Law:
I = V / R_total = 6.0 V / 36 ohm = 0.17 A
The current flowing in R₁ is the same as the total current, since they are in series:
I₁ = 0.17 A
The current flowing in R₂ is also the same, since they are in series:
I₂ = 0.17 A
To calculate the total power consumed by R₁ and R₂, we use the formula:
P = I²R
For R₁:
P₁ = I₁²R₁ = (0.17 A)²(12 ohm) = 0.35 W
For R₂:
P₂ = I₂²R₂ = (0.17 A)²(24 ohm) = 0.71 W
The total power consumed by both resistors is:
P_total = P₁ + P₂ = 0.35 W + 0.71 W = 1.06 W
Answer:
1. The total resistance of the two resistors:
Since the resistors are connected in parallel.
Total resistance = R₁ + R2
Total resistance = 12 ohm + 24 ohm
Total resistance = 36 ohms
2. The total current flowing in the circuit:
I = V/R
where ,
I is current,V is voltage (6.0 V) and r is resistance.I = 6.0 V /36 ohm
I = 0.17 amperes
3. The current flowing in R₁
Since he two resistance R₁ and R₂ are connected in series. The current flowing through these two will be equal to the total current flowing in the circuit.
Current flowing in R₁ = 0.17 A
4. The current flowing in R2 = total current flowing in the circuit:
The current flowing in R₂ = 0.17 A.
5. The total power consumed by R₁ and R₂
power consumed by R₁
P = I²R
P = (0.17)²/12
P = 0.0289/12
P = 0.35 (approx)
Now, power consumed by R₂
P = (0.17)² × 24
P = 0.0289 × 24
P = 0.70 (approx)
Total power = power consumed by R₁ + R₂
Total power = 0.35 + 0.70
Total power consumed = 1.05 W
A clown figurine is located 21.0 cm in front of a thin lens that has a focal length of 17.0 cm. Where would the image appear, and would it be real or virtual?
15.2 cm, virtual
89.3 cm, real
111 cm, real
−65.2 cm, virtual
A boy of mass 60 kg and a girl of mass 40 kg are together and at rest on a frozen pond. What is the initial momentum of the girl?
A. 100 kgm/s
B. 40 kgm/s
C. 10 kgm/s
D. 0 kgm/s
Answer:
Explanation:
The answer is D. 0 ;
As We know when the net external force on an isolated system is absent then the total linear momentum of the system remains conserved.
=> By Conservation of linear Momentum of the system;
=> P1=P2 i.e initial momentum= final momentum;
=>if final momentum is '0' that is they are in rest position velocity is 0;
So momentum is 0 By p=mv;
Hence initial momentum will be zero;
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The initial momentum of the girl can be calculated using the formula:
p = mv
where p is the momentum, m is the mass, and v is the velocity.
Since the boy and the girl are at rest on the frozen pond, their initial velocity is zero. Therefore, the initial momentum of the girl is:
p = mv = (40 kg)(0 m/s) = 0 kgm/s
So, the answer is D. 0 kgm/s.
6.1 Instantaneous communication. In your own words, explain why you
cannot send a message instantaneously using the mechanism of ex-
periment 6.1. If quantum mechanics were deterministic rather than
probabilistic, yet the distant atoms still always left from opposite
exits of a stern gerlach analyzer, would you then be able to send a message instantaneously?
What if the operator of the left-hand Stern-Gerlach analyzer were
somehow able to force his atom to come out of the + exit?
We can see here in one's own words, instantaneous communication would still not be conceivable even if quantum mechanics were predictable and the results of measurements could be predicted in advance. This is because, even if they were entangled, any attempt to change the state of one atom would inevitably change the state of the other atom.
What is quantum mechanics?The behavior and interaction of particles at the atomic and subatomic scales is the subject of quantum mechanics, a subfield of physics. It offers a mathematical framework for describing the probabilistic nature of physical occurrences in the microscopic world as well as the wave-particle duality of matter.
Until they are measured or observed, particles in quantum mechanics do not have fixed positions or attributes, and the measurement process might have an impact on the system being examined.
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Jeremiah is conducting an investigation about the water cycle. He is given the following materials:
a lamp
a glass jar that contains water
plastic wrap
Describe how Jeremiah can arrange these materials to create a model that shows the processes by which water is cycled from a lake into the atmosphere and back to the lake. Be sure to identify what each material represents in the model.
Answer:
The water cycle outlines the continuous water movement in liquid, solid and gaseous state between locations on the Earth's surface.
The glass jar represents the lake while the atmosphere is represented by the space above the water, and the sky is represented by the (clear) plastic wrap
Arrangement description and Processes;
The processes of the water cycle includes;
Evaporation;
Condensation
Precipitation
Sublimation
Runoff
Infiltration
The arrangement of the materials is as follows;
Place the glass jar (the lake) containing water and the lamp (the Sun) side by side, such that the lamp light shines on the water surface
Cover the glass jar by wrapping the plastic wrap (the sky) around it to prevent the escape of water vapor when the water is hot.
Switch on the lamp so that it heats the water by radiation heat transfer
Observed processes;
The processes demonstrated by the above experiment includes;
1) Evaporation: As the water in the glass jar becomes warmer, the level of the water in the jar can be observed to decrease slightly due to evaporation
2) Condensation: Fog formation, Clouds
When hotter, the water surface as seen through the clear plastic wrap becomes less clearer due to evaporation, and condensation of the vapor while floating above the water surface, similar to the clouds seen in the sky.
3. Precipitation: Rain;
The clear plastic wrap covering the top of the glass jar, prevents the movement of the vapor further away, such that the tiny condensed vapor gather together, to form big droplets under the plastic wrap that falls back into the jar, which is similar to the process of rainfall
The above processes are repeated as more water evaporates from the jar condenses on the plastic wrap and falls back into the jar, showing the process by which water is recycled from the lake into the atmosphere and back to the lake.
Explanation:
Two vectors with a magnitude of 5 and 12 have a dot product equal to -6. Find the angle between the vectors to the
nearest degree.
the angle between vectors is 1
let, vector A,B and |A| =5 , |B| =12
According to dot product,
A.B = |A| |B| cos∝
-6 = 5x12cos∝
cos∝ = 0.99
nearly equal to 1
hence the angle between A and B is 1
_______, ________, and ________ are renewable resources.
biomass energy, hydropower, and coal energy
hydropower, coal energy, and wind energy
biomass energy, hydropower, and wind energy
biomass energy, coal energy, and wind energy
✎help its an exam✎ ☕︎if any links I WILL REPORT☕︎
Answer:
biomass energy, hydropower and wind energy
A ball is initially at rest and travels 7.8 m. The ball travels at an acceleration of 6.4 m/s². What is the final velocity of the ball? Give your answer to 1 decimal place.
The final velocity of the ball to one decimal place is approximately 10.0 m/s.
What is the final velocity of the ball?From the third equation of motion:
v² = u² + 2as
Where v is final velocity, u is initial velocity, a is acceleration and s is the distance covered.
Given that:
Ball was initially at rest, initial velocity u = 0acceleretaion a = 6.4 m/s²distance traveled s = 7.8 mFinal velocity v = ?Plug the given values into the abovr formula and solve for the final velocity v.
v² = u² + 2as
v² = 0² + ( 2 × 6.4 m/s² × 7.8 m )
v² = 2 × 6.4 m/s² × 7.8 m
v² = 99.84 m²/s²
v = √( 99.84 m²/s² )
v = 10.0 m/s
Therefore, the final velocity is 10.0 m/s.
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When a 102 g mass is hung on a spring it stretches 4.0 cm. The spring is then set in SHM by stretching it a further 6.0 cm and then releasing it.
a) Calculate the force required to stretch the spring 6.0 cm.
Answer:
1.53 N
Explanation:
The force required to stretch a spring is given by Hooke's law: F = k*x, where F is the force, k is the spring constant, and x is the displacement from the equilibrium position.
In this problem, we are given the mass and the displacement of the spring, but we need to find the spring constant before we can calculate the force.
The spring constant can be found using the equation k = F/x, where F is the force required to stretch the spring and x is the corresponding displacement.
Given that the 102 g mass stretches the spring by 4.0 cm, we have:
k = F/x = (mg)/x = (0.102 kg)(9.8 m/s^2)/(0.04 m) = 25.5 N/m
where g is the acceleration due to gravity.
Now, to calculate the force required to stretch the spring by 6.0 cm, we use the same equation with the new displacement:
F = kx = (25.5 N/m)(0.06 m) = 1.53 N
Therefore, the force required to stretch the spring by 6.0 cm is 1.53 N.
A block is dropped from rest. It takes a time t, to fall the first third of the distance. How long does it take to fall the entire distance? a) √3t₁ b) 3t₁ c) 9t₁ d) None of the above to = 0 ti t₂ TITI Vo = 0 S₂ = X S₁ = x/3
The time it will take the block to fall the entire distance is (a) √3t₁.
How to determine time in motion?Use the equations of motion to solve this problem. The equation to use is:
S = (1/2)gt²
where S = distance, g = acceleration due to gravity, and t = time.
First find the time it takes to fall the first third of the distance. The distance fallen is S₁ = x/3, so:
x/3 = (1/2)gt₁²
Solving for t₁:
t₁ = √((2x)/(3g))
Now, find the time it takes to fall the entire distance. The total distance is S₂ = x, so:
x = (1/2)gt₂²
Solving for t₂:
t₂ = √((2x)/g)
Substituting x with 3S₁:
t₂ = √((6S₁)/g)
Substituting t₁:
t₂ = √((4x)/(3g)) = √(4/3)t₁
Therefore, the answer is (a) √3t₁.
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Ritalin and the pain medication Demerol have a high risk of dependence but may be used for medicinal purposes under a doctor's supervision. These substances are _____ of the CSA list.
Ritalin and Demerol are both controlled substances that have a high risk of abuse and dependence.
What is the list?Schedule II drugs are believed to have a high abuse potential that could lead to severe psychological or physical dependence. They do, however, occasionally have other known medical applications and can be prescribed by a licensed healthcare provider.
Ritalin is an example of a stimulant, whereas Demerol is an example of an opioid. Thus the drugs that have been mentioned here are drugs that are strictly controlled.
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Find the induced voltage in the conductor of the Figure below where B = 0.04 ay Tan
U = 2.5 sin 103t az m/s.
The induced e.m.f is -0.02sin(10^3t) (V) which is option D
What is Induced Voltage?Induced voltage refers to the electrical voltage that is generated in a conductor or coil due to a changing magnetic field.
This phenomenon is known as electromagnetic induction and is the basis for many electrical devices such as generators and transformers.
Induced voltage can be calculated using Faraday's law, which states that the induced electromotive force (EMF) is equal to the rate of change of magnetic flux.
The induced voltage can be either positive or negative depending on the direction of the changing magnetic field and the orientation of the conductor or coil.
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What is the inertia of motion?
THE INABILITY OF A BODY TO CHANGE ITS STATE OF MOTION BY ITSELF ⚡
._Its_Ńämüđà_.The tendency of matter to resist changes in its velocity or direction of motion is known as the inertia of motion. One of the cornerstones of traditional mechanics, it is also known as the law of inertia.
What is the inertia of motion? This principle states that, without an external force, an object at rest tends to remain at rest and an object in motion tends to maintain its current speed and direction. This means that until a force acts on the moving item to cause it to modify its motion, it will continue to proceed in a straight path and at a constant speed due to inertia of motion.
An object's mass affects how much inertia of motion it possesses. An object's inertia of motion increases with bulk, making it more challenging to alter its speed or direction of motion. This feature of matter has a wide range of practical uses, including predicting how moving objects will behave and creating and building systems that need to precisely regulate motion and forces.
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You decide to go skiing but fall over. As you are attempting to get back up, you see a child start to head down the hill straight for you. If the coefficient of friction between the child and the snow is assumed to be 0, and the child appears to be 20 m above you when they start down the mountain, and the incline of the mountain is 31 degrees, how long do you have to get up and out of the way before you and the child collide?
The time taken to get up and out of the way before you and the child collide is 2.82 s.
What is the time taken to get up?The time taken to get up and out of the way before you and the child collide is calculated as follows;
s = v + ¹/₂at²
s = v + ¹/₂(g sin (31)t²
where;
v is the initial velocitys is the displacementt is the time of motionThe time taken to get up is calculated as;
20 = 0 + ¹/₂(9.8 sin (31)t²
20 = 2.524t²
t² = 20/2.524
t² = 7.925
t = 2.82 s
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3. Would you expect a system with objects that have an equal amount of positive and negative
charge to have a large amount of electric potential energy? Why or why not?
Yes, I would expect a system with objects that have an equal amount of positive and negative charge to have a large amount of electric potential energy.
Why I will expect equal positive and negative chargeThis is because the electric potential energy of a system of charges is proportional to the product of the charges and inversely proportional to the distance between them. When positive and negative charges are brought close together, the electric potential energy of the system increases because the charges are attracted to each other due to their opposite charges.
As the charges get closer together, the electric potential energy of the system increases even more, because the charges are closer to each other and their attraction is stronger.
Therefore, when there are equal amounts of positive and negative charges in a system, the electric potential energy of the system will be high because there will be many oppositely charged pairs of particles that are close together and attracting each other strongly.
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Which of the following occurs when an oscillating spring system reaches its equilibrium position?
The kinetic energy is at its maximum.
The restoring force is at its maximum.
The potential energy is at its maximum.
The velocity is 0.
Answer: Velocity=0
Explanation: At equilibrium the spring system is not moving.
2.
How did Robert Boyle demonstrate that sound needs a medium through which to travel?
He found that an alarm watch in a vacuum did not make a
sound.
He found that the speed of sound varied under different
conditions.
MacBook Air
He found that an alarm watch under water did not make a
sound.
He recorded the time that distant pistol fire was heard.
Robert Boyle demonstrated that sound needs a medium through which to travel by observing that an alarm watch in a vacuum did not make a sound. Option 1 is the answer.
Sound and mediumSound is a form of energy that results from the vibration of matter. When an object vibrates, it creates sound waves that travel through a medium and can be perceived by the human ear.
A medium is a substance or material through which waves can travel. In the case of sound, air, water, and solids such as metal or wood can serve as a medium. Without a medium, sound cannot propagate because there are no molecules to vibrate and transmit the waves.
Robert Boyle demonstrated that sound needs a medium through which to travel by observing that an alarm watch in a vacuum did not make a sound. This led him to conclude that sound requires a medium, such as air or water, to propagate.
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What do you call burning organic waste. SAMBSIO?
Burning organic waste is often referred to as "incineration.
What is an "incineration?It is a process in which organic waste is burned at high temperatures to convert it into ash and gas. Incineration is often used as a method of waste management to reduce the volume of waste and to eliminate potentially harmful organic materials, such as medical waste or hazardous chemicals.
However, incineration can also produce air pollution and greenhouse gas emissions, and there are concerns about the impact of incineration on human health and the environment. As a result, many communities and governments are exploring alternative methods of waste management, such as recycling and composting.
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A model of a helicopter rotor has four blades, each 3.40 m long from the central shaft to the blade
trip. The model is rotated in a wind tunnel at 550 rev/min. (a) What is the linear speed of the blade
tip, in m/s? (b) What is the radial acceleration of the blade tip expressed as a multiple of the
acceleration of gravity, g?
The linear speed of the blade tip is approximately 114 m/s.
The radial acceleration of the blade tip is approximately 488 times the acceleration of gravity, g.
(a) To calculate the linear speed of the blade tip, we need to convert the rotational speed from revolutions per minute (RPM) to radians per second. One revolution is equivalent to 2π radians, so the angular velocity of the rotor is 550 rev/min x (2π/60) = 57.54 radians/second.
The linear speed of the blade tip is then the product of the angular velocity and the length of the blade, giving us 57.54 radians/second x 3.40 m = 195.6 m/s. The blade tip is only a small fraction of the total length of the blade, so we can assume that the linear speed of the blade tip is approximately equal to the linear speed of the rotor at a radius of 3.40 m. Therefore, the linear speed of the blade tip is approximately 114 m/s.
(b) The radial acceleration of the blade tip is given by the formula ar = rω², where r is the radius of the blade and ω is the angular velocity of the rotor in radians per second. Substituting in the values given, we get ar = (3.40 m) x (57.54 radians/second)² = 11,976 m/s². To express this in terms of g, we divide by the acceleration due to gravity, g = 9.81 m/s², giving us ar/g ≈ 488.
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HELP!!! You have two substances, both of which have the same boiling point (or attraction between their molecules).
The first substance is made from molecules that are small (just a few atoms bonded together), and the second substance is made from mol that are larger (many atoms bonded together).
How can it be possible for two such different molecules to yield substances with the same boiling point? Describe the kinds of intermolecu attractions that must be involved and any other properties of the molecules that could cause this result.
Despite having different molecular sizes, two substances can have the same boiling point due to the presence of intermolecular attractions that compensate for the difference in molecular weight.
What is the explanation for the above response?Despite having different molecular sizes, two substances can have the same boiling point due to the presence of intermolecular attractions that compensate for the difference in molecular weight.
These intermolecular attractions, such as London dispersion forces, dipole-dipole interactions, or hydrogen bonding, play a crucial role in determining a substance's boiling point. For example, the larger molecules may have more surface area for London dispersion forces to act upon, while smaller molecules may have more polar groups for dipole-dipole interactions or hydrogen bonding.
As a result, these different types of intermolecular forces can offset each other, leading to substances with different molecular sizes having the same boiling point.
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An object vibrates with a frequency of 2200 Hz to produce sound waves that travel through air with a speed of 340 m/s. Adjacent compressions (i.e., wavelengths) in the sound wave are a distance of meters apart.
The adjacent compressions in the sound wave are 0.155 meters apart.
This distance is also known as the wavelength of the wave. We are given the frequency of the vibration and the speed of sound in air. The formula for wavelength is:
wavelength (λ) = speed of sound (v) / frequency (f)
We are given the frequency of the sound wave as 2200 Hz and the speed of sound through air as 340 m/s.
Plugging these values into the formula gives:
λ = 340 m/s / 2200 Hz = 0.155 meters
Therefore, adjacent compressions (i.e., wavelengths) in the sound wave are a distance of 0.155 meters apart.
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HELP ASAP
The specific heat capacity of solid copper metal is 0.385 J/g-K. How many joules of heat are needed to raise the temperature of a 1.55-kg block of copper from 33.0 °C to 99.9 °C?
3.71 × 10^−6J
39.9 J
3.99 × 10^4J
0.00371 J
2.69 × 10^5 J
IT IS A CHEMISTRY QUESTION BUT WAS PUT WITH PHYSICS BY MISTAKE SORRY
Answer: 3.99•10⁴ J
Explanation:
The Heat Formula is: Q = m • C • ΔT
Your given C, m, T₀, and T
C = 0.385 J/g•K
m = 1.55 kg or 1,550 g
T₀ = 33.0 °C
T = 99.9 °C
(ΔT = T - T₀)
Your only remaining variable is Q, heat, so you can now plug in your values to solve.
Q = (1550)(0.385)(99.9 - 33.0)
(ΔT(°C) = ΔT(K) because the conversion is linear)
Q = 39,922.575 J
or
3.99•10⁴ J
78. A rocket takes off from Earth and reaches a speed of 100 m/s in 10.0 s. If the exhaust
speed is 1500 m/s and the mass of fuel burned is 100 kg, what was the initial mass of the rocket?
Answer:
5866.9 kg
Explanation:
We can use the conservation of momentum to solve this problem. The momentum of the rocket and fuel system is conserved, so:
Initial momentum = Final momentum
The initial momentum of the system is zero since the rocket is at rest initially. The final momentum is the momentum of the rocket after burning the fuel. We can find the final momentum using the rocket equation:
Δv = ve * ln(m0 / mf)
where Δv is the change in velocity (100 m/s), ve is the exhaust speed (1500 m/s), m0 is the initial mass of the rocket and fuel system (what we want to find), and mf is the final mass of the rocket and fuel system (m0 - 100 kg).
Solving for m0, we get:
m0 = mf * exp(Δv / ve) = (m0 - 100 kg) * exp(100 / 1500)
Simplifying this equation, we get:
m0 = 100 kg / (1 - exp(100 / 1500))
m0 = 5866.9 kg (rounded to four significant figures)
Therefore, the initial mass of the rocket and fuel system was approximately 5866.9 kg.
Sean throws a baseball at an angle of 25 relative to the ground at a speed of 23m/s. What is the maximum height the ball will achieve? How long will it be in the air? How far away does Kelly need to be to catch the ball?
Answer:
To solve this problem, we can use the equations of motion for projectile motion:
- Vertical displacement: Δy = v₀sinθt - 1/2gt²
- Vertical velocity: v = v₀sinθ - gt
- Time of flight: T = 2v₀sinθ/g
- Horizontal displacement: Δx = v₀cosθt
where v₀ is the initial speed, θ is the angle of projection, g is the acceleration due to gravity (9.81 m/s²), t is the time of flight, and Δy and Δx are the vertical and horizontal displacements, respectively.
First, we can find the maximum height by using the equation for vertical displacement:
Δy = v₀sinθt - 1/2gt²
At the maximum height, the vertical velocity is zero, so we can find the time of flight by setting the vertical velocity equation to zero:
v = v₀sinθ - gt = 0
Solving for t, we get:
t = v₀sinθ/g
Substituting this into the equation for vertical displacement, we get:
Δy = v₀sinθ(v₀sinθ/g) - 1/2g(v₀sinθ/g)²
Simplifying, we get:
Δy = (v₀²sin²θ)/(2g)
Substituting the given values, we get:
Δy = (23²sin²25)/(2*9.81) ≈ 29.4 m
So the maximum height is approximately 29.4 meters.
Next, we can find the time of flight using the equation for time of flight:
T = 2v₀sinθ/g
Substituting the given values, we get:
T = 2*23*sin25/9.81 ≈ 3.5 s
So the time of flight is approximately 3.5 seconds.
Finally, we can find the horizontal displacement using the equation for horizontal displacement:
Δx = v₀cosθt
Substituting the given values, we get:
Δx = 23*cos25*3.5 ≈ 64.3 m
So Kelly needs to be approximately 64.3 meters away to catch the ball.
A team of astronauts is on a mission to land on and explore a large asteroid. In addition to collecting samples and performing experiments, one of their tasks is to demonstrate the concept of the escape speed by throwing rocks straight up at various initial speeds. With what minimum initial speed esc will the rocks need to be thrown in order for them never to "fall" back to the asteroid? Assume that the asteroid is approximately spherical, with an average density =2.02×106 g/m3 and volume =1.71×1012 m3.Recall that the universal gravitational constant is =6.67×10−11 N·m2/kg2.