Elementary Astronomy - Chapter 5 - Modules of Motion

If you are told that a 20 kilogram object is raised by 10 meters, you know that

the mass of the object is 20 kilograms

An ion rocket engine produces 1 Newton of thrust. What acceleration can it give to a space probe with a mass of 1000kg?

0.001 m/s^2

Suppose that you lift an object by exerting an upward force of 12 newtons on it. If gravity exerts a force of 10 Newtons downward on the object, what is the total force on the object?

2 Newtons

What total force will cause an object with a mass of 5kg to gain 10 meters per second every second?

50 Newtons

Suppose that you drop two objects from the same height at the same time. Both objects are heavy enough to be unaffected by air resistance and one object is twice as heavy. Who predicted that both objects would hit the ground at the same time?

Galileo

When Newton calculated the magnitude of the acceleration of Earth's Moon, and compared it to the acceleration of falling objects on the surface of the Earth, he found that

The Moon's acceleration was smaller.

A book, weighing 10 Newtons, sits on a table. Which of the following pairs of forces is an action-reaction pair.

The force that exerts on the table and the force that the table exerts on the book.

The International Space Station (ISS) is in a roughly circular orbit near the surface of the Earth, moving at around 5 miles per second. Suppose that a rocket pushes it and quickly increases its speed to 6 miles per second. The ISS will then

follow an ellipse that rises and then descends again.

Freely falling objects with different masses fall with the same acceleration because

gravity exerts more force on the more massive object.

If the acceleration of an object is zero, its speed

is not changing

According to Newton's Law of Gravity, the gravitational attraction of the Earth for other objects, such as the Moon, apples on trees and space shuttles in low earth orbit,

is smaller for objects farther from the Earth but never vanishes entirely.

Galileo said that a moving object with nothing pushing or pulling on it will always

keep moving at the same speed

Aristotle said that a moving earthly or 'mundane' object with nothing pushing or pulling on it will always

slow down and stop

An artificial satellite such as the International Space Station stays up because

the Earth curves out from under it as fast as it falls.

The force that acts on a rocket because its engine is firing is exerted by

the exhaust from the rocket.

When Newton calculated the magnitude and direction fo the acceleration for a planet that was following Kepler's Laws, he found that the direction of the acceleration was

toward the Sun.