 |
| 1 | |
What do we call the tendency of a body at rest to remain at rest or a body in motion to remain in motion? |
| | A) | gravity. |
| | B) | the “action-reaction” law |
| | C) | The tendency of a person to stay in bed in the morning. |
| | D) | inertia. |
|
|
|
| 2 | |
If you see a body in space that is not moving in a straight line at constant speed, what can you say about it? |
| | A) | It must be an artificial satellite. |
| | B) | There must be a force acting on it |
| | C) | It is not subject to any outside forces. |
| | D) | None of the above |
|
|
|
| 3 | |
Which of the following objects (A-D) are accelerating? A. an object at rest / B. an object in motion in a straight line at a constant speed / C. an object in motion in a straight line with increasing speed / D. an object moving in a circle at constant speed. |
| | A) | A only. |
| | B) | All but A. |
| | C) | C only. |
| | D) | Both C and D. |
|
|
|
| 4 | |
How can we mathematically express Newton's law of gravity? (In the following, F is the force of Gravity, G is a constant; m and M are the masses or two bodies (such as the Earth and the Sun); and r is the distance between the centers of mass the two bodies.) |
| | A) | F = GMm/r |
| | B) | F = GMm/r2 |
| | C) | F = GMm/r3 |
| | D) | F = Gm2M/r2 |
|
|
|
| 5 | |
If the distance between two masses is tripled, the gravitational force between them is |
| | A) | increased by a factor of 3. |
| | B) | increased by a factor of 9. |
| | C) | decreased by a factor of 3 |
| | D) | decreased by a factor of 9. |
|
|
|
| 6 | |
If an object's mass (M) is doubled, the gravitational force between it and other objects will be |
| | A) | increased by a factor of 2. |
| | B) | increased by a factor of 4. |
| | C) | decreased by a factor of 2. |
| | D) | decreased by a factor of 4. |
|
|
|
| 7 | |
The gravitational force exerted by the Sun on the Earth is ____ the gravitational force exerted by the Earth on the Sun. |
| | A) | greater than |
| | B) | less than |
| | C) | equal to |
| | D) | unrelated to |
|
|
|
| 8 | |
What is Newton's first law of motion? |
| | A) | A body continues in a state of rest or uniform motion in a straight line unless made to change that state by forces acting on it. |
| | B) | Force equals mass times acceleration, F=ma. |
| | C) | Every mass exerts a force on any other mass that is proportional to the product of the masses divided by the square of the distance between them. |
| | D) | When two bodies interact, they create equal and opposite forces on each other. |
|
|
|
| 9 | |
What is Newton's second law of motion? |
| | A) | A body continues in a state of rest or uniform motion in a straight line unless made to change that state by forces acting on it. |
| | B) | Every mass exerts a force on any other mass that is proportional to the product of the masses divided by the square of the distance between them. |
| | C) | Force equals mass times acceleration, F=ma. |
| | D) | When two bodies interact, they create equal and opposite forces on each other. |
|
|
|
| 10 | |
What is Newton's third law of motion? |
| | A) | When two bodies interact, they create equal and opposite forces on each other. |
| | B) | Force equals mass times acceleration, F=ma. |
| | C) | Every mass exerts a force on any other mass that is proportional to the product of the masses divided by the square of the distance between them. |
| | D) | A body continues in a state of rest or uniform motion in a straight line unless made to change that state by forces acting on it. |
|
|
|
| 11 | |
What does surface gravity measure? |
| | A) | The tendency of a planet's surface to collapse under gravity. |
| | B) | How fast an object needs to go to escape a planet's gravity. |
| | C) | The attraction between the surfaces of two massive objects. |
| | D) | The gravitational attraction at a planet's or star’s surface. |
|
|
|
| 12 | |
How are mass and weight different? |
| | A) | There is no difference, they are the same. |
| | B) | Weight is a measure of how much gravity pulls an object; mass is how much matter the object has. |
| | C) | Mass is the amount of matter an object contains; weight is how much matter an object contains. |
| | D) | Weight is the amount of matter an object contains; mass is the type of matter an object is made of |
|
|
|
| 13 | |
If your mass is 60 kilograms on Earth, what is it on the Moon? |
| | A) | 0 kilograms, because the Moon has no gravity. |
| | B) | 60 kilograms, because mass does not depend on gravity. |
| | C) | 120 kilograms, because the Moon’s gravity is greater than Earth’s. |
| | D) | 360 kilograms, because the Moon is a spherical object. |
|
|
|
| 14 | |
If a barbell weighs 10 pounds on the Moon, what would it weight on Earth? |
| | A) | 1.67 pounds. Surface gravity on the Moon is 1/6 that on the Earth. |
| | B) | 10 pounds. Gravity is the same on the Earth and the Moon. |
| | C) | 30 pounds. Surface gravity on the Earth is 3 times that on the Moon. |
| | D) | 60 pounds. Surface gravity on the Earth is 6 times that on the Moon. |
|
|
|
| 15 | |
What does escape velocity measure? |
| | A) | The gravitational attraction at a planet's surface. |
| | B) | How fast an object needs to go to escape a planet's gravity. |
| | C) | How far away an object needs to be to escape a planet's gravity. |
| | D) | How fast an object needs to go to escape hostile space aliens. |
|
|
.