Under what condition is the angular momentum of an object conserved? -If there are no torques acting on it. -If there is no net torque acting on it. -If it is a point particle. -If there is no net force acting on it

Answer:

Newton’s first law states that an object will remain at rest or in motion at a constant velocity unless acted on by a net external force. Newton’s second law states that the force acting on an object is equal to its mass times its acceleration. When a rocket hits an asteroid, the asteroid will remain still until acted upon by the force of the rocket. The force of impact will depend on the mass and acceleration of the rocket.

Explanation:

Newton’s first law, also known as the law of inertia, states that an object at rest remains at rest, or if in motion, remains at a constant velocity unless acted on by a net external force. This means that a rocket will remain still until a force is applied to move it. Once it’s in motion, it won’t stop until a force is applied.

Newton’s second law states that the force acting on an object is equal to its mass times its acceleration (F=ma). This means that the more mass an object has, the more force is needed to move it. During a rocket launch, the engines burn the propellant to fuel the rocket, using it all up until it is gone. Thus, the rocket’s mass becomes smaller as the rocket ascends. So, in keeping with Newton’s second law of motion, the rocket’s acceleration increases as its mass decreases.

When a rocket hits an asteroid, both Newton’s first and second laws come into play. The asteroid will remain still until acted upon by an external force (the rocket). The force of impact will depend on the mass and acceleration of the rocket.

Determine the amount, location, and direction that the force is required to maintain the balance of the bar: [Ans: 106 North, 0.675 Left at 49"] G0 N 70 N.

If all three of a following three conditions are true, a solid subjected by three forces with opposing lines or action is in equilibrium: There are coplanar action lines (in the same plane) The lines of activity have intersected (they cross at the same point) These forces combine to form a vector that sums to zero.

An object is now in equilibrium or moving at a constant speed if it is subjected to two equal and opposing forces. A object resting on the a horizontal surface serves as an illustration of this. The object's weight is equal to and in opposition to the upward resistive force.

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The required mass of the asteroid in terms of Earth's mass will be 0.088 M.

It is given that the asteroid becomes 22% longer than it is as a result of collision.  

From the information given, the length of the day is 2π rad/ω. According to the angular momentum theory,

where,

ω is the Earth's angular rotation rate

Applying conservation of angular momentum to the Earth and asteroid results in,

2/5 M R² ω₁ = (mR² + 2/5 MR²) ω₂

m = 2/5 M(ω₁ - ω₂)/ω₂

T₂ = 1.22T

Above equation can be written as,

1/ω₂ = 1.22/ω₁

ω₁ = 1.22 ω₂

ω₁ - ω₂/ω₂ = 0.22

m = 2/5 (0.22) M = 0.088 M

where,

m is the mass of the asteroid

M is the mass of the earth

Thus, the mass of the asteroid in terms of earth's mass is calculated.

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Refraction occurs when light encounters an air-to-water interface or boundary where the coefficient of refraction shifts, causing the light to shift orientation as it travels from one medium to another.

The angle of incidence and the variation in the coefficients of refraction between the two surfaces determine how much refraction takes place.

Some of the light will be reflected into the air and the remainder will be refracted into the water if the angle of contact is less than the crucial angle.

Total internal reflection takes place and all of the light is mirrored back into the air if the angle of contact exceeds the critical angle.

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The best estimate for the magnitude of the gravitational field at the surface of planet Krypton is 7.98 times that of Earth's, assuming the same surface density. This is because the gravitational field is proportional to the mass and inversely proportional to the square of the radius.

The magnitude of the gravitational field at the surface of a planet depends on its mass and radius. Planet Krypton has a radius 4.44 times larger and a mass 2.22 times greater than Earth. Using the formula for the gravitational field, which is G*M/R^2, where G is the gravitational constant, M is the mass, and R is the radius, we can estimate the gravitational field at the surface of Krypton. By plugging in the values for Krypton and Earth and assuming the same surface density, we get a value of 7.98 times the gravitational field on Earth. This means that objects on the surface of Krypton will experience a stronger gravitational force than those on Earth.

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Answer:

1.25 m/s^2

Explanation:

got it right on khan

The Burrows-Wheeler transform (BWT) is a data compression method that groups similar characters together by reordering a string of letters. As a result, the converted string has longer same-character runs.

than the original string. The local repeating patterns of the original string are exposed in the BWT. The BWT operates by cyclically rotating the original string and lexicographically sorting the rotations. The BWT is built from the final character of each rotation. The BWT exposes the local repeating patterns in the original string by grouping related characters together. This characteristic makes string compression simpler since same-character runs may be encoded more efficiently. As a result of lexicographically sorting the rotations, the BWT obtains longer same-character runs.

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Answer:

The relative velocity of X with respect to X is zero, as X can not move with respect to itself. However, if the question was asking for the relative velocity of Y with respect to X, then it would be calculated by subtracting the speed of X from the speed of Y, which would be 15km/hrs.

The electric field amplitude of the electromagnetic wave is approximately [tex]6.3 * 10^5[/tex] volts per meter.

The electric field amplitude (E) of an electromagnetic wave can be calculated from the magnetic field amplitude (B) using the equation:

E = c * B

Where c is the speed of light in a vacuum, which is approximately 3 x [tex]10^8 \\[/tex]meters per second.

Using the given magnetic field amplitude of 2.1mT, we can convert it to SI units of Tesla by multiplying it by[tex]10^-3[/tex]:

B = 2.1 mT = 2.1 x 10^-3 T

Then, we can calculate the electric field amplitude by multiplying the magnetic field amplitude by the speed of light:

[tex]E = c * B = (3 x 10^8 m/s) * (2.1 x 10^-3 T) ≈ 6.3 x 10^5 V/m[/tex]

Therefore, the electric field amplitude of the electromagnetic wave is approximately 6.3 x 10^5 volts per meter.

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The line integral is zero for path A, proportional to the magnitude for path B, and depends on the angle for path C.

The line basic of a vector field addresses the amount of scalar results of the vector field and minuscule relocation along a way or bend.  For a uniform attractive field, the line vital along way A, which is opposite to the attractive field, is zero. Along way B, which is lined up with the attractive field, the line vital is non-zero and is relative to the size of the attractive field and the length of the way.

Along way C, which is bended and not equal or opposite to the attractive field, the line basic relies upon the point between the way and the attractive field at each point. In the event that the point is consistent along the way, the line essential will be corresponding to the size of the attractive field and the length of the way.

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Answer:

engaging in more exercise

Explanation:

Maladaptive means not providing an adequate or appropriate adjustment to the environment or situation. Therefore the question is asking which is Not a bad way to respond to stress.

The amount work done by the monster is 4176 J.

Work is said to be done when a force moves an object through a distance.

To calculate the work done by the monster,  we use the formula below

Formula:

Where:

From the question,

Given:

Susbtitute these values into equation 1

Hence, the work done is 4176 J.

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Explanation:

If ignoring air friction, the horizontal component will not change.

If taking air friction into account, then horizontal component will decay.

The horizontal component of the velocity of a projectile changes with time due to the force of gravity acting on the projectile. Initially, the projectile will have a constant horizontal velocity, as there is no net force acting on it in the horizontal direction.

However, once the projectile is fired, the force of gravity will begin to act on it, causing its horizontal velocity to decrease. This decrease in horizontal velocity is due to the fact that gravity is an acceleration, which means that it will cause the projectile to slow down over time.

As the projectile moves further away from the point of launch, its horizontal velocity will continue to decrease until it reaches its terminal velocity. At this point, the horizontal velocity of the projectile will remain constant and will not change with time.

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The graph obtained from plotting log xc (capacitive reactance) vs log (frequency) is typically a straight line. The slope of the graph represents the power of the frequency dependence on the capacitive reactance.

If the data supports the theoretical dependence between xc and frequency, then the slope of the graph will be equal to -1/C, where C is the capacitance of the capacitor.

The relationship between the capacitive reactance and frequency is that capacitive reactance decreases with increasing frequency. To calculate the capacitance of the capacitor using the intercept of the graph,

We can use the equation log(xc) = log(C) - log(f), where xc is the capacitive reactance, C is the capacitance, and f is the frequency. The intercept of the graph will be log(C).

By taking the antilogarithm of the intercept, we can find the capacitance. The percentage difference between this value and the expected value of the capacitor can then be calculated using the formula:

% difference = [(measured value - expected value) / expected value] x 100%.

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Answer:

The bottom.(support)

Explanation: Because everything is based on the support if the support fails everything fails, so if the support fails usually it is nearest to the ground, it will fall first.

Answer: The bottom because that's what's carring all the weight of the building.

Explanation:

Answer:

The average speed of the lizard was 2.25 meters per second.

Explanation:

To find the average speed of the lizard, we need to use the formula:

Average speed = Total distance ÷ Total time

First, we need to find the total distance the lizard ran. He ran 3.0 meters to his friend's house and then ran back halfway, so he ran a total distance of:

3.0 + (1/2)3.0 = 4.5 meters

Next, we need to find the total time it took the lizard to run this distance. We're told that it took 2.0 seconds in total, so the time for the first leg of the journey (from the rock to his friend's house) must have been half of that, or 1.0 second. The time for the second leg (from his friend's house back to the rock) must also have been 1.0 second.

Now we can plug in the values into the formula:

Average speed = Total distance ÷ Total time

Average speed = 4.5 meters ÷ 2.0 seconds

Average speed = 2.25 meters per second

Explanation:

Average speed =3.0 × 2.0

= 6.0

The velocity of the airplane is approximately 69.84 m/s.

To find the velocity of the airplane flying at a standard sea level with a density of 1.23 kg/m³, static pressure of 1.01 x  [tex]10^{5}[/tex] N/m², and a pitot-static tube reading of 1.04 x  [tex]10^{5}[/tex] N/m², we can use Bernoulli's equation, which is applicable for steady, incompressible, and irrotational flow.

The Bernoulli's equation is given by: P₁ + 0.5ρV₁² + ρgh = P₂ + 0.5ρV₂² + ρgh₂ Since we're considering only horizontal flight, the potential energy terms (ρgh) can be canceled out. Additionally, since the pitot-static tube measures the total pressure (dynamic pressure + static pressure), P₂ is the total pressure (1.04 x  [tex]10^{5}[/tex] N/m²), and P₁ is the static pressure (1.01 x 10^5 N/m²).

The density ρ is given as 1.23 kg/m³. Now, rearrange the equation to solve for V₁ (the velocity of the airplane): V₁² = 2(P₂ - P₁) / ρ Substitute the given values: V₁² = 2(1.04 x [tex]10^{5}[/tex] N/m² - 1.01 x  [tex]10^{5}[/tex] N/m²) / 1.23 kg/m³ Calculate the result: V₁² = 2(3 x 10 N/m²) / 1.23 kg/m³ V₁² ≈ 4878.05 m²/s² Now, take the square root to find the velocity: V₁ = √4878.05 m²/s² ≈ 69.84 m/s

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The color of an object is determined by the wavelengths of light that it absorbs and reflects.

The chemical composition and physical structure of an object influence how it interacts with light. For example, a red apple appears red because it reflects red wavelengths of light and absorbs other colors. However, the way we perceive color is also influenced by our visual system, which includes our eyes and brain.

Our eyes have photoreceptor cells that detect different wavelengths of light and send signals to the brain, which interprets these signals as colors. Additionally, factors such as lighting conditions and the colors of surrounding objects can affect how we perceive the color of an object. Therefore, both the nature of the object and our visual system contribute to how we perceive its color.

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1a. The change in government spending that is needed to close the inflationary gap is 5 billion dollars, and b. the change in taxes that is needed to close the inflationary gap is 40 billion dollars.

a. To answer this question, we need to use the following formula:

ΔY = MPC / (1 - MPC) * ΔG

where:

   ΔY is the change in output (in this case, the inflationary gap of 15 billion dollars)

   MPC is the marginal propensity to consume, which is given as 0.75

   ΔG is the change in government spending

To find the change in government spending, we can rearrange the formula as follows:

ΔG = ΔY * (1 - MPC) / MPC

Plugging in the given values, we get:

ΔG = 15 billion * (1 - 0.75) / 0.75

= 15 billion * 0.25 / 0.75

= 5 billion dollars

So the change in government spending that is needed to close the inflationary gap is 5 billion dollars.

b. To find the change in taxes, we can use the following formula:

ΔT = MPC / (1 - MPC) * ΔY - ΔG

where ΔT is the change in taxes

Plugging in the given values, we get:

ΔT = 0.75 / (1 - 0.75) * 15 billion - 5 billion

= 3 * 15 billion - 5 billion

= 40 billion dollars

Therefore, the change in taxes that is needed to close the inflationary gap is 40 billion dollars.

For question 2:

a. To answer this question, we can use the following formulas:

ΔY = MPC / (1 - MPC) * ΔG

where:

   ΔY is the change in output (in this case, the recessionary gap of 100 billion dollars)

   MPC is the marginal propensity to consume, which is given as 0.8

   ΔG is the change in government spending

To find the change in government spending, we can rearrange the formula as follows:

ΔG = ΔY * (1 - MPC) / MPC

Plugging in the given values, we get:

ΔG = 100 billion * (1 - 0.8) / 0.8

= 100 billion * 0.2 / 0.8

= 25 billion dollars

So the change in government spending that is needed to close the recessionary gap is 25 billion dollars.

b. To find the change in taxes, we can use the following formula:

ΔT = - MPC / (1 - MPC) * ΔY + ΔG

where ΔT is the change in taxes.

Plugging in the given values, we get:

ΔT = -0.8 / (1 - 0.8) * 100 billion + 25 billion

= -4 * 100 billion / 5 + 25 billion

= -80 billion + 25 billion

= -55 billion dollars

Therefore, the change in taxes that is needed to close the recessionary gap is a decrease of 55 billion dollars. This means that taxes would need to be reduced by 55 billion dollars to stimulate consumption and investment, and help close the recessionary gap.

Similarly you can use the same formulae for the other 3 questions:

3. a.  the change in government spending = 10 billion dollars;

b. the change in taxes = 800 billion dollars.

4. a. change in government spending = 5 billion dollars

b. the change in taxes  = 5 billion dollars

5. a. change in government spending = 120 billion dollars

b. change in taxes = 30 billion dollars

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To generate the observed effect, the professor most likely altered the phase relationship of the speakers. Interference between waves of the same frequency and amplitude can occur in sound waves,

resulting in either constructive or destructive interference. The lecturer altered the time of the waves arriving at different spots in the classroom by modifying the phase relationship of the speakers. When the waves were in phase, they constructively added together and generated a loud tone for certain pupils. When the waves were out of phase, they destructively cancelled each other out and generated no sound for the pupils who had initially heard the booming tone. This is known as interference, and it happens not just in sound waves but also in other forms of waves, such as light waves. as light and water waves. Understanding interference is important in many areas of physics, including acoustics, optics, and communications.

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An aluminium wire's cross-sectional area is[tex]A = 3.1 * 10^{-5} m^{2}[/tex], and its length is L = 0.17 m.

The resistance of an aluminum wire is given by the formula:

[tex]R = \frac{\rho L}{A}[/tex]

Where R = resistance, ρ = resistivity of aluminum, L = length of wire, and A = cross-sectional area of wire.

So that we can solve for A, we can rearrange the equations as follows

[tex]A =\frac{ \rho L}{R}[/tex]

Plugging in the given values, we have:

[tex]A =\frac{ (1.7 * 10^{-8} Ohm*m)(L)}{(0.1 Ohm)}[/tex]

Solving for L,

[tex]L = \frac{(0.1 Ohm)(A)}{(1.7 * 10^{-8} Ohm*m)}[/tex]

We also know that the mass of the aluminum wire is 54 g. The following formula determines a wire's mass:

[tex]m = \rho AL[/tex]

In order to find A, we can rearrange the equation as follows:

[tex]A = \frac{m}{(\rho L)}[/tex]

Plugging in the given values, we have:

[tex]A =\frac{ (54 g)}{((1.7 *10^{-8} Ohm*m)(L))}\\A = 3.1 * 10^{-5} m^{2}[/tex]

Combining the two equations, we obtain:

[tex]L =\frac{ (54g)(0.1 Ohm)}{((1.7 * 10^{-8} Ohm*m)(A))}[/tex]

L = 0.17 m

Therefore, the cross-sectional area  is [tex]A = 3.1 * 10^{-5} m^{2}[/tex] and L = 0.17 m is the length of an aluminium wire.

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B is the best choice. The Sun's most stable phase of its life is around halfway through it right now.

The following statement defines the Sun's lifetime: "The Sun is only one of the innumerable stars that make up our Universe, and like all stars, it has a lifespan that is comprised of formation, main sequence, and final death. This lifetime started at 4.6 billion years ago and will last for another 4.5 to 5.5 billion years, after which it will run out of hydrogen and helium, swell to a red giant, and finally collapse as a white dwarf."But the sun will exhaust its hydrogen supply in around 5 billion years. From the creation of our solar system 4.5 billion years ago, when our star was in its most stable phase of its life cycle, this has remained the case. The sun will eventually emerge from this stable state once all the hydrogen has been used up.

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The force exerted by the air on the front surface of the book with dimensions 15.0 cm x 25.0 cm can be calculated using the formula F = P x A, where P is atmospheric pressure (100,000 Pa) and A is the area of the book (15.0 cm x 25.0 cm = 375 cm2).

Therefore, the force exerted by the air is F = 100,000 Pa x 375 cm2 = 37,500,000 N. This means that the air exerts a force of 37,500,000 N on the front surface of the book. This force is a result of the pressure differential between the surrounding air and the book surface.

The atmospheric pressure is pushing the air molecules away from the book surface, thus creating a force on the book surface. This force keeps the atmospheric pressure in balance and helps to prevent the book from being crushed.

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It requires 48000π kg*m of work to pump all the water out of the tank. To find the work required to pump all the water out of the tank, first find the volume:

1. Determine the volume of the cone-shaped tank using the formula V = (1/3)πr²h, where V is the volume, r is the base radius, and h is the height. In this case, r = 1 meter and h = 12 meters. V = (1/3)π(1)²(12) = 4π cubic meters

2. Calculate the total weight of the water in the tank using the density of water, which is 1000 kg/m³. Weight = volume × density = 4π × 1000 kg = 4000π kg

3. Determine the distance each infinitesimally small slice of water needs to be pumped. Since the water is pumped out from the top, we can consider the distance to be the height of the tank (12 meters).

4. Calculate the work done to pump out all the water using the formula W = weight × distance. W = 4000π kg × 12 meters = 48000π kg*m

So, it requires 48000π kg*m of work to pump all the water out of the tank.

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The current needed for the solenoid is 599.17 A.

To determine the current needed for the solenoid, we can use the equation for the magnetic field strength inside a solenoid: B = μ₀ * n * I

where B is the magnetic field strength, μ₀ is the permeability of free space [tex](4π x 10^-7 Tm/A)[/tex], n is the number of turns per unit length of the solenoid, and I is the current.

First, let's calculate the number of turns per unit length of the solenoid:

n = N / L

where N is the total number of turns and L is the length of the solenoid. Since the solenoid has a single layer of wire, we can use the equation:

N = π * r² * ρ / (d² * p)

where r is the radius of the solenoid (0.75/2 = 0.375 m), ρ is the resistivity of the wire (assuming it's a Type II superconductor with zero resistance, we can take ρ to be zero), d is the diameter of the wire (2.50 mm = 0.0025 m), and p is the pitch of the wire (equal to the diameter of the wire, so p = 0.0025 m).

Substituting in these values, we get:

N = π * (0.375 m)² * 0 / (0.0025 m)² * 0.0025 m

N = 1414.16

So the number of turns per unit length is:

n = 1414.16 / 1.8 m

n = 785.65 turns/m

Now we can substitute in the values for B and n, and solve for I:

B = μ₀ * n * I

I = B / (μ₀ * n)

Substituting B = 1.5 T and the values for μ₀ and n, we get:

[tex]I = 1.5 T / (4π x 10^-7 Tm/A * 785.65 turns/m)[/tex]

I = 599.17 A

So the current needed for the solenoid is 599.17 A.

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When the width of the slit is decreased in a single-slit experiment, the width of the central band would increase. This phenomenon is known as diffraction.

A single-slit experiment is an experiment in which a beam of light is allowed to pass through a narrow slit and fall on a screen placed at some distance from the slit. The light waves are diffracted as they pass through the slit, and the diffracted waves interfere with one another, producing a pattern of light and dark bands on the screen. The diffraction pattern produced by a single-slit experiment is affected by the width of the slit.

When the width of the slit is decreased, the width of the central band increases. This is because the waves diffracted through a narrow slit spread out more, causing the central band to become wider. To put it another way, the narrower the slit, the more the light waves are diffracted. This diffraction effect produces a wider central band. Therefore, the width of the central band increases when the slit width is decreased.

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The value that is measured by the slope of a position-time graph is velocity. It is a vector quantity that measures the rate of change of an object's position.

It is calculated by taking the slope of a position-time graph which can be done by finding the change in position (displacement) divided by the change in time. Velocity is determined by the distance an object moves in a given period of time and its direction of motion. An object's velocity is constantly changing as it accelerates, decelerates, and changes direction.

The formula for velocity is velocity = displacement/time.

Velocity can be represented by a line on the graph that is parallel to the x-axis and has a slope that is equal to the velocity of the object.

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complete question: Please select the word from the list that best fits the definition: Value that is measured by the slope of a position-time graph.

a) Momentum

b) Velocity

c) Acceleration

d) Displacement

The work done by the external agent to bring the plates  of a capacitor closer together is about 0.625 μJ.

The work done by an external agent to move the plates of a capacitor is given by:

W = (1/2) * C * (Vf² - Vi²)

where W is the work done, C is the capacitance, Vf is the final voltage, and Vi is the initial voltage.

Initially, the capacitance of the capacitor is 5.0 μF and it is charged to 5 μC. Therefore, the initial voltage across the capacitor is:

Vi = Q / C = 5 μC / 5.0 μF = 1 V

When the plates are brought closer together, the capacitance of the capacitor becomes 10 μF, but the charge on the capacitor remains the same. Therefore, the final voltage across the capacitor is:

Vf = Q / C' = 5 μC / 10 μF = 0.5 V

Substituting these values into the equation for work, may get:

W = (1/2) * 5.0 μF * (0.5² - 1²) = 0.625 μJ

Therefore, the work done by the external agent to bring the plates closer together would be about 0.625 μJ.

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It does not experience any changes in speed during its orbit. So, the correct option is: an object on a perfectly circular orbit has an eccentricity of 0.

An object on a perfectly circular orbit has an eccentricity of 0.What is an orbit?An orbit is the path of an object or particle that is moving in space, generally around a more massive object, due to the influence of gravity.What is eccentricity?The eccentricity of an elliptical orbit is the ratio of the distance between the foci of the ellipse to the length of its major axis.What happens to speed during an orbit?During an orbit, the speed of an object can vary depending on its distance from the massive object it is orbiting.According to the question above, an object on a perfectly circular orbit has an eccentricity of 0.

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Newton's third law of motion states that every action has an equal and opposite reaction. Similarly, when a rocket moves, it exerts a force on the gases to propel them backward. This in turn exerts an equal and opposite reaction force to move the rocket forward.