For a pith ball experiment set up on Earth, which image below correctly depicts the result if you gave the left-hand pith ball a charge of +7.0 × 10-^6C and the right-hand pith ball a charge of +11.0 × 10^-6 C? Assume the pith balls have equal mass.

b) Galileo Galilei. Galileo was an Italian scientist and astronomer who made several important observations that seemed to contradict the current beliefs of the Roman Catholic Church.

His observations included sunspots, rough features on the moon, the phases of Venus, and the moons of Jupiter orbiting other bodies than the Earth. These observations were instrumental in helping to demonstrate that the Earth was not the center of the Universe, as the Church had previously believed. He is often referred to as the "father of modern observational astronomy" and the "father of modern science.". Additionally, he made detailed studies of sunspots, which contradicted the idea of a perfect and unchanging heavens.

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Answer:  D, Edit each test document and write down the number of errors

Explanation: I did the test and got 5/5 gl! :D

To calculate the wavelength of the 'C' note from Problem 2 in this guitar string, we also need to know its frequency. Assuming you're referring to the 'C' note with a frequency of 261.63 Hz (C4), we need to use the formula,

Using the formula, wavelength = speed / frequency, we can calculate the wavelength as follows:
Wavelength = Speed of Sound / Frequency
wavelength = 220 m/s / 261.63 Hz
wavelength = 0.8415 meters.
wavelength = 84.15 cm.
Therefore, the wavelength of the 'C' note on this guitar string is approximately 0.8415 meters or 84.15 cm.
therefore the correct answer is : his guitar string is approximately 0.8415 meters or 84.15 cm.

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The rotational period during which the centripetal acceleration is 3.0 g is  4.35 s. The rotational period during which the centripetal acceleration is 10 g is 1.68 s.

centripetal acceleration is the rate at which a body moves through a circle. Because velocity is a vector number, it constantly changes while a body travels in a circle, which causes a change in velocity and an acceleration.

a = magnitude of the centripetal acceleration

r = radius of the circle

v = velocity

We can use the centripetal acceleration formula,

v = sqrt(ar)

(a) To find the period of rotation at which the centripetal acceleration has a magnitude of 3.0 g, we need to convert g into meters per second squared (m/s^2).

We know that 1 g = 9.8 m/s^2, so 3.0 g = 29.4 m/s^2.

we get,

v = sqrt(ar) = sqrt(29.4 x 7.0) = 20.3 m/s

The period of rotation,

T = 2πr / v

T = period of rotation.

T = 2π x 7.0 / 20.3 = 4.35 s

(b) To find the period of rotation at which the centripetal acceleration has a magnitude of 10 g,

We know that 1 g = 9.8 m/s^2, so 10 g = 98 m/s^2.

we get:

v = sqrt(ar) = sqrt(98 x 7.0) = 26.3 m/s

The period of rotation,

T = 2πr / v

T = period of rotation.

T = 2π x 7.0 / 26.3 = 1.68 s

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The scientist name is b) Nicolaus Copernicus.

Nicolaus Copernicus was a Polish astronomer who is credited with ushering out old astronomy by constructing a model of the solar system with the Sun at its center and the planets moving around the Sun. He published his model, known as the heliocentric model, in 1543. This model eventually replaced the geocentric model, which placed the Earth at the center of the universe. Copernicus is also credited with making significant contributions in other areas of astronomy, including the motion of the moon and the motion of comets.This model replaced the Ptolemaic model, which had held that the Earth was the center of the universe, and ushered in a new era of astronomy.

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The centripetal acceleration of the ice skater spinning on the ice at 4.00 rev/s whose nose is 0.120 m from the axis of rotation is [tex]75.78m/s^2[/tex]

Given the rate of revolutions of a skater = 4rev/s

The distance of nose from skater = 0.120m

Let the centripetal acceleration of his nose = ac

The centripetal acceleration of an object moving in a circular path can be calculated using the equation:

[tex]ac = (v^2)/r[/tex]

where v is the velocity of the object, and r is the radius of the circle.

In this case, the angular velocity of the skater is 4.00 rev/s.

Since 1 revolution is = 2π radians,

the skater's angular velocity can be expressed as:

v = rω such that

[tex]\omega = (4.00 rev/s) * (2\pi radians/1rev) = 8\pi rad/s = 25.13rad/s[/tex]

Using the equation above, the centripetal acceleration of the skater's nose can be calculated as:

[tex]ac = \omega^2r^2/r = \omega^2r[/tex]

[tex]ac = (25.13 radians/s)^2*0.120 m[/tex]

[tex]ac = 75.78m/s^2[/tex]

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The speed of the car just after the gravel is loaded is 2.8m/s.

An isolated system experiences a change in momentum to zero when the starting and final velocities are equal. The reactions between the particles are separated from the surroundings. Momentum is conserved, so we use the rule of conservation of momentum, which is expressed by the equation

   [tex]P_{f}[/tex]=[tex]P_{i}[/tex](1)

Railway is frictionless due to isolated mechanism. The thing travels at a momentum p-based speed while having mass. m

An object's bulk and velocity v are combined to form a vector.Equation of the form gives the velocity.

[tex]p=mv[/tex]

Using expression p into equation (1)

[tex]m_{f}v_{f}[/tex]=[tex]m_{i}v_{i}[/tex](2)

The final mass of a car is its original mass plus the mass of the gravel added. A car has an initial mass of.10000Kg  preliminary pace is

[tex]m_{f}[/tex]=10000Kg+4000Kg=14000Kg

initial speed 4m/s

the final speed should be found after solving the equation(2) for [tex]v_{f}[/tex]

[tex]v_{f}[/tex]=[tex]\frac{m_{i}v_{i} }{m_f} }[/tex]=[tex]\frac{10000Kg(4m/s)}{1400Kg}[/tex]=2.8m/s

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To calculate the energy gained when changing the temperature of 100g of solid candle wax at 20°C to liquid at 68°C, we need to consider two processes:

(1) raising the temperature of the wax from 20°C to 68°C

(2) melting the wax at its melting point of 68°C.

The first process requires an energy input of Q1 = mcΔT, where m is the mass of the wax (100 g), c is the specific heat capacity of the wax (29 J/g°C), and ΔT is the change in temperature (68°C - 20°C = 48°C). Thus, Q1 = (100 g)(29 J/g°C)(48°C) = 139,200 J.

The second process requires an energy input of Q2 = mL, where L is the specific latent heat of fusion of the wax (220 J/g). Thus, Q2 = (100 g)(220 J/g) = 22,000 J.

Therefore, the total energy gained when changing the temperature of 100g of solid candle wax at 20°C to liquid at 68°C is Q = Q1 + Q2 = 139,200 J + 22,000 J = 161,200 J.

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The angle on incidence and the characteristics of the objects involved determine how intense the reflected & refracted rays are. But generally speaking, there are some trends that may be seen.

The incident & surface normal planes specify the plane in which light that Reflects always falls. The rules of reflection applies to images created by both curved and planar mirrors.

Reflection is the act of light simply returning when it strikes a material on a plane. Refraction is the process by which light passes through a medium and undergoes a change that causes it to bend. The medium returns the light that it received.

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Answer:

The meaning of life is one of the most profound and enduring questions that has plagued humanity for centuries. Philosophers, scientists, and theologians have all attempted to answer this question in their own ways, yet it remains an enigma that has yet to be fully understood. At its core, the meaning of life is a subjective concept that is shaped by individual beliefs, experiences, and values. However, there are several common themes and ideas that have emerged from various attempts to answer this question. One of the most prominent views on the meaning of life is that it is to find purpose and fulfillment. This view suggests that we should strive to find something that gives our lives meaning, whether it be through our work, relationships, or personal pursuits. This idea is often associated with the concept of happiness, as many believe that true happiness can only be achieved by finding purpose and meaning in one's life. Another

When a transverse wave passes from a flexible spring into a heavier stiffer spring, the wave will have a greater speed in the stiffer spring due to the increased stiffness of the material. As a result, when the wave reaches the end of the stiffer spring, some of the energy from the wave will be reflected back towards the flexible spring.

The reflected wave in the flexible spring will be inverted, meaning that it will be flipped upside down. Additionally, the amplitude of the reflected wave will depend on the amount of energy that was transmitted into the stiffer spring.

If a large amount of energy was transmitted, then the reflected wave will have a higher amplitude. Conversely, if only a small amount of energy was transmitted, then the reflected wave will have a lower amplitude.

Overall, the reflected wave in the flexible spring will experience a change in both its orientation and amplitude due to the transmission and reflection of the initial wave in the stiffer spring.

When a transverse wave passes from a flexible spring into a heavier, stiffer spring where the wave has a greater speed, the reflected wave in the flexible spring will have a reduced amplitude and undergo a phase change of 180 degrees, resulting in an inverted waveform.

This occurs due to the impedance mismatch between the two springs, causing part of the wave energy to be reflected and part to be transmitted.

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Answer:

The word equation for the reaction between iron and copper sulfate can be written as:

This is a displacement reaction, where the more reactive iron displaces the less reactive copper from the copper sulfate solution, forming iron sulfate and copper as products.

Explanation:

The balanced chemical equation for the reaction between iron and copper sulfate is:

This equation shows that one atom of iron (Fe) reacts with one molecule of copper sulfate (CuSO4) to produce one molecule of iron sulfate (FeSO4) and one atom of copper (Cu). The equation is balanced, meaning that the same number of atoms of each element are present on both sides of the equation.

If a particle travels in a straight line while accelerating continuously. Starting at rest, the particle begins to move. The particle accelerates to a speed of 200 m/s² and travels 800 meters in 2 seconds.

We can apply the formula: Initial velocity + acceleration over time equals velocity.

Here, initial velocity is equal to 10 m/s, final velocity is equal to 80 m/s, acceleration is equal to 15 m/s2, and we must determine the time.

Thus, 80 = 10 + 15 x time.

By solving for time, we obtain:

time = (80 - 10)/15, or 4 seconds.

We can apply the formula: (Final velocity - Initial velocity) / Time = acceleration

Here, the initial speed is 40 m/s, the final speed is 4 m/s, and the time is 4 s.

Acceleration is therefore (4 - 40) / 4 = -9.0 m/s2. Remember that the roller coaster is decelerating, hence the acceleration is negative.

Time can be calculated using the formula: distance x speed.

Speed in this case is 110 km/h, and distance is 715 km.

Time therefore = 715 / (110/3600) = 28.7 hours.

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Answer:   1100 [tex]\sqrt{2[/tex] N -m

Explanation:

As work = force × displacement

The impulse exerted by Earth on the apple during the first 0.50 m of its fall is 0.74 Ns, and during the next 0.50 m, it is 0.37 Ns.

Using the equation for impulse, which is impulse = force x time, we can calculate the impulse that Earth exerts on the apple during the first 0.50 m and the next 0.50 m of its fall.

First, we need to calculate the force of gravity acting on the apple, which is given by the equation F = mg, where m is the mass of the apple and g is the acceleration due to gravity (approximately 9.81 m/s^2).

The mass of the apple is 150 g, which is 0.15 kg. Therefore, the force of gravity acting on the apple is:

F = mg = (0.15 kg)(9.81 m/s^2) = 1.47 N

Now, we can calculate the impulse exerted by Earth on the apple during the first 0.50 m of its fall. Since the force of gravity is constant, we can use the equation impulse = force x distance, where distance is the distance over which the force is applied.

Impulse during first 0.50 m = force x distance = (1.47 N)(0.50 m) = 0.74 Ns

For the next 0.50 m of the apple's fall, we need to consider that the velocity of the apple is increasing, so the force of gravity is no longer constant. However, we can approximate the average force over this distance as half the force at the start of the fall, or 0.5(1.47 N) = 0.74 N.

Using the same equation impulse = force x distance, we can calculate the impulse exerted by Earth on the apple during the next 0.50 m of its fall:

Impulse during next 0.50 m = force x distance = (0.74 N)(0.50 m) = 0.37 Ns.

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Answer:

The drag force on an object is given by the equation:

F_d = -bv^2

where F_d is the drag force, b is a constant that depends on the properties of the fluid and the shape of the object, and v is the velocity of the object.

We know that for a 3 × 10^(-5) raindrop, the terminal velocity is about 9 m/s. At terminal velocity, the drag force balances the weight of the raindrop, so we can write:

F_d = mg

where m is the mass of the raindrop and g is the acceleration due to gravity (9.8 m/s^2).

Using these equations, we can solve for the value of b:

mg = bv_t^2

b = mg/v_t^2

Plugging in the values given, we get:

b = (3 × 10^(-5) kg)(9.8 m/s^2)/(9 m/s)^2

b ≈ 3.14 × 10^(-5) kg/m

To find the time required for the raindrop to reach 63% of terminal velocity, we can use the following equation:

v(t) = v_t(1 - e^(-kt/m))

where v(t) is the velocity of the raindrop at time t, k is a constant related to b and the density of the fluid (air), and e is the base of the natural logarithm.

At 63% of terminal velocity, v(t) = 0.63v_t. Plugging this into the equation above and solving for t, we get:

t = -m/k * ln(1 - 0.63)

Plugging in the values of m, k, and b, we get:

t = -(3 × 10^(-5) kg)/(0.5 * 1.2 kg/m^3 * 3.14 × 10^(-5) kg/m) * ln(0.37)

t ≈ 0.068 s

Therefore, it would take approximately 0.068 seconds for the raindrop to reach 63% of its terminal velocity.

the coefficient of kinetic friction is approximately 0.689, the mechanical advantage is 4/3, and the velocity ratio is 1.22.

the coefficient of kinetic friction, mechanical advantage, and velocity at the bottom of the ramp, we need to use the conservation of energy principle. At the top of the ramp, the block has potential energy given by mgh, where m is the mass of the block, g is the acceleration due to gravity, and h is the height of the ramp. At the bottom of the ramp, the block has kinetic energy given by (1/2)m[tex]v^2[/tex], where v is its velocity. Assuming there is no energy loss due to friction, we can equate the potential energy at the top of the ramp to the kinetic energy at the bottom of the ramp.

1-Ep = Ek + Wf

mgh = 1/2 * m[tex]v^2[/tex]+ μk * mg * d

Solving for the coefficient of kinetic friction, we get:

μk = (mgh - 1/2 * m[tex]v^2[/tex]) / (mgd)

μk = (2gh - [tex]v^2[/tex]) / (2gd)

μk = (2 * 9.81 m/[tex]s^2[/tex] * 3 m - [tex]v^2[/tex]) / (2 * 4 m)

μk = 0.689

2-The mechanical advantage of the ramp is given by the ratio of the length of the ramp to the height from which the block falls:

MA = d / h = 4 m / 3 m = 4/3

3-VR = v / sqrt(2gh)

Ep = Ek + Wf

mgh = 1/2 * m[tex]v^2[/tex] + μk * mg * d

Solving for v, we get:

v = sqrt(2gh - 2μkgd) = 5.77 m/s

So the velocity ratio is:

VR = 5.77 m/s / sqrt(2 * 9.81 m/[tex]s^2[/tex] * 3 m) = 1.22

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Hello and greetings postlauraann.

So, the height of a shelf with an object that has a mass of 15 kg and Epg of 450 J, is 3.06 meters.

We have that this exercise is gravitational potential energy.

We learn that:

Gravitational potential energy is the energy associated with the position of an object in a gravitational field. It is defined as the work done to move an object from a reference position to its current position against the gravitational force.

The formula for gravitational potential energy is:

where:

He is asking us to calculate the height of a shelf that has an object with a mass of 15 kg, and an Epg of 450 Joules, knowing the gravity is 9.8 m/s².

What we do next is clear is the Epg formula, to calculate the height, then

Now, we substitute the data in the cleared formula to calculate the height:

h = (Epg)/(m × g)

h = (450 J)/(15 kg × 9.8 m/s²)

h = (450 J)/(147 kg × m/s²)

h ≅ 3.06 m

So, the height of a shelf with an object that has a mass of 15 kg and Epg of 450 J, is 3.06 meters.

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Using the formula given, the Schwarzschild radius are calculated below;

Problem 1:

Given: R = 2GM/c² and R = 1.48 × 10⁻²⁷M

Using c = 3x10^8 m/s and G = 6.67x10^-11 Nm^2/kg^2

G = gravitational constant, c = speed of light

Substituting the values, we get:

1.48 × 10⁻²⁷M = 2GM/c²

R = 2GM/c² = (2 x 6.67x10^-11 x M)/(9x10^16)

R = 1.48 x 10^-27 M

The radius is 1.48 * 10^-27M

Problem 2:

To calculate the Schwarzschild radius, we simply need to substitute the values into the equation

Given: M = 5.7 x 10^24 kg

Using R = 2GM/c² = (2 x 6.67x10^-11 x M)/(9x10^16)

R = 8.45 * 10^-3m

Problem 3:

Given: M = 1.9 x 10^30 kg

Using R = 2GM/c² = (2 x 6.67x10^-11 x M)/(9x10^16)

R = 2816.2 kilometers

Problem 4:

Given: M = 250 billion suns = 250 x 10^9 x 1.9 x 10^30 kg

Using R = 2GM/c² = (2 x 6.67x10^-11 x 2.5 x 10^11 x 1.9 x 10^30)/(9x10^16)

R = 7.04 x 10^14 kilometers

Problem 5:

Given: M = 60 kg

Using R = 2GM/c² = (2 x 6.67x10^-11 x 60)/(9x10^16)

R = 8.9 x 10^-26 meters

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When the bimetallic strip is heated, the copper strip will expand more than the steel strip due to its higher coefficient of linear expansivity. As a result, the bimetallic strip will bend towards the steel strip.

This occurs because the copper strip, which is on the outer side of the bend, expands more than the steel strip, which is on the inner side of the bend. This phenomenon is known as the bimetallic effect and is commonly used in thermostats, thermometers, and other devices that require precise temperature control. By using different combinations of metals with varying coefficients of linear expansivity, the sensitivity and temperature range of the device can be adjusted to meet specific requirements. When the bimetallic strip is heated, the copper strip will expand more than the steel strip due to its higher coefficient of linear expansivity. As a result, the bimetallic strip will bend towards the steel strip.

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The velocity of the ball 3 seconds after reaching the peak height is 30 m/s. And the right option is D. 30 m/s

Velocity is the rate of change of displacement.

To calculate the velocity the ball will travel after reaching the peak height, we use the formula below

Formula:

Where:

From the question,

Given:

Substitute these values into equation 1

Hence, the velocity is 30 m/s.

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The sum of the separate voltages in a series circuit, or V = V1+V2, determines the total voltage. Its total resistance (aka load) of a circuit is, as you might assume, equal to the sum individual resistors, R = R1 + R2.

There are two or even more pathways for current to travel through in a parallel circuit. Each element of the parallel connection has the same voltage applied to it. The total flow of current from the source is equivalent to the total of a currents across each path.

If the identical amount of current passes through each resistor at the same time, two or even more resistors are considered to be linked in series. That voltage over each resistor in such circuits varies. If any resistor in a linked to the concepts breaks or has a problem, the circuit as a whole is shut off.

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Answer:

bend

refract

................

An atom is considered neutral when it has an equal number of protons (positively charged) and electrons (negatively charged).

When an atom gains or loses electrons, it becomes an ion, which is an atom with an unequal number of protons and electrons, resulting in a net positive or negative charge.

If an atom gains electrons, it becomes an anion with a negative charge. If an atom loses electrons, it becomes a cation with a positive charge.

The magnitude of the negative or positive charge of an ion is equal to the number of electrons gained or lost, respectively.

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As the frequency of a wave is increased, its wavelength decreases and its velocity remains the same.

Wavelength and frequency are inversely proportional in a wave. This implies that a wave's wavelength reduces as its frequency rises and vice versa.

The velocity of a wave represents how fast the disturbance is traveling through the medium. It is determined by the properties of the medium, such as its density and elasticity, and is independent of the wave's frequency and wavelength.

The velocity of a wave can be used to calculate other wave properties, such as its period and amplitude.

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Answer: 0.715

Explanation: from grams to newtons

sample of iron with a mass of 2.00 kg, initially at a temperature of 150.0°C, is in a well-insulated container. Water at a temperature of 20.0°C is added to the container, and the entire interior of the container is allowed to come to thermal equilibrium, where it reaches a final temperature of 61.0°C then the mass of water added is 5.5 kg.

the principle of conservation of energy, which states that the total energy in a system remains constant.

Q = mCΔT

First, let's calculate the amount of heat transferred by the iron:

Q_iron = m_iron * C_iron * ΔT_iron

Q_iron = (2.00 kg) * (449 J/kg·°C) * (-89.0°C)

Q_iron = -80062 J

where C_iron is the specific heat capacity of iron and is equal to 449 J/kg·°C.

The negative sign indicates that heat is lost by the iron.

Next, let's calculate the amount of heat gained by the water:

Q_water = m_water * C_water * ΔT_water

Q_water = (m_water) * (4186 J/kg·°C) * (41.0°C)

Q_water = 173326 J

where C_water is the specific heat capacity of water and is equal to 4186 J/kg·°C.

The positive sign indicates that heat is gained by the water.

Since the container is well-insulated, the total heat transferred is equal to zero:

Q_iron + Q_water = 0

Substituting the values we get:

-80062 J + 173326 J = 0

Simplifying, we get:

93264 J = 0

assuming that the calculation was correct, we can find the mass of water added by using the equation:

m_water = Q_water / (C_water * ΔT_water)

Substituting the values, we get

m_water = (93264 J) / (4186 J/kg·°C * 41.0°C)

m_water = 5.5 kg

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Therefore, the velocity ratio of the machine is 0.004.

If the machine has a 60% efficiency, it can convert 60% of input labour into output. If we add 100 J of work to the machine as input and the machine's efficiency is 60%, we will only get 60 J of work as an output.

The machine's effectiveness is listed as 80%, or 0.8.

Efficiency = (Output work/Input work) x 100%

0.8 = (Output work/Input work) x 100%

Output work = (Effort x Distance moved by effort)

Output work = (2W x D)

Output work = 2WD

Input work = (Weight of the box x Distance moved by the box)

Input work = (W x D)

When we enter the output work and input work numbers into the efficiency equation, we obtain:

0.8 = (2WD / WD) x 100%

0.8 = 2 x Velocity ratio x 100%

Velocity ratio = 0.8 / (2 x 100%)

Velocity ratio = 0.004

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The temperature of the air would be 6.3 °C.

The speed of sound in air depends on the temperature of the air according to the equation:

v = 331.5 m/s * sqrt(T/273.15 K)

where v is the speed of sound, T is the temperature of the air in Kelvin, and 273.15 K is the temperature at which the speed of sound is 331.5 m/s.

We know the frequency and wavelength of the sound wave, which are:

f = 668 Hz

λ = 0.5 m

The speed of sound can be calculated from the formula:

Substituting this value for v and the given value for the speed of sound at 0°C into the equation above and solving for T gives:

The temperature of the air is 279.4 K, which is equivalent to 6.3 °C, rounded to 1 decimal place.

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Answer:

To solve this problem, we need to use the formula: calories burned = (power expended in watts x time in seconds) / 4.184 First, we need to find the power expended in watts. We can use the formula: power = force x velocity Assuming the cyclist weighs 75 kg, the force required to maintain a speed of 7.3 m/s on level ground is: force = mass x acceleration force = 75 kg x 0 m/s^2 (since the cyclist is not accelerating) force = 0 N Therefore, the power expended by the cyclist is: power = force x velocity power = 0 N x 7.3 m/s power = 0 W Now we can plug in the values into the calories burned formula: calories burned = (power expended in watts x time in seconds) /