# Concepts to Describe the Asteroid's Motion

[1] What concepts would you use to describe the asteroid's motion?

[2] If the asteroid is moving at a constant speed in its orbit, does this also mean it is moving at a constant velocity? Explain your answer.

[3] Based on your answer above, is the asteroid accelerating? Explain.

[4] What force acts to hold this massive object in orbit around the Sun? What direction does this force act?

[5] This asteroid's motion is affected by many different massive objects. Rank the following in order of increasing influence: the Sun, Mars, Jupiter, and other asteroids. Explain your answer clearly and specify the main determining factor for each body.

[6] Assume this asteroid has the shape of a sphere. A rock sitting on the surface of the asteroid has a weight of 100 newtons. What would the weight of this rock be if it were moved to a distance above the surface equal to the radius of the asteroid? It may be helpful to draw a picture to better visualize what is going on. How is the mass of the rock affected by its change in position?

[7] At some point in its orbit our asteroid is moving with a speed of 20 kilometers per second. Determine the kinetic energy of the asteroid assuming it has a mass of 1000 kilograms. Be sure your answer is in the correct units of energy.

[8] If the distance from the Sun varied during our asteroid's orbit, would its kinetic energy change? Would its potential energy change? Would the total energy (sum of kinetic and potential energy) of the asteroid change?

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[1] What concepts would you use to describe the asteroid's motion?

To describe the Asteroids motion one would consider its position in its orbit, its distance from the Sun and its instantaneous velocity at any point in time

[2] If the asteroid is moving at a constant speed in its orbit, does this also mean it is moving at a constant velocity? Explain your answer.

Constant speed does not mean constant velocity. Speed is a scalar quantity so only has a magnitude. Velocity is a more informative measurement so has both magnitude and direction so is a so called Vector quantity. Magnitude can stay constant so the Asteroids speed can indeed remain constant, however, the Asteroids direction can change so its velocity is not necessarily constant

[3] Based on your answer above, is the asteroid accelerating? Explain.

Acceleration is another vector quantity and so has both magnitude and direction. In more formal terms acceleration is defined as the rate of change of velocity (not rate of change of speed) so if the velocity changes due to the direction of motion changing then the Asteroid can be ...

#### Solution Summary

The solution discusses the concepts to describe the asteroid's motion.