Question | Answer |
Which one of the following describes an object that is accelerating? | A car going around a circular track at a steady 100 miles per hour. |
State each of Newton's three laws of motion. For each law, give an example of its application. | 1st Law-An object moves at constant velocity unless a net force acts to change its speed or direction. Example: A passenger on a plane is unable to feel any sensation of the plane. 2nd Law-Force is equal to mass times acceleration. Example:throwing a ba |
Which of the following examples describes a situation where a car is experiencing a net force? | The car is making a gradual turn. |
Compared to its angular momentum when it is farthest from the Sun, Earth’s angular momentum when it is nearest to the Sun is | the same |
Suppose that two objects collide. Which of the following things is NOT the same both before and after the collision? | the total temperature of the objects |
When a spinning ice skater pulls in his arms, he spins faster because _________. | his angular momentum must be conserved, so reducing his radius must increase his speed of rotation |
Which of the following describes a speed, according to an astronomer? | 10 light-years per 1 million years |
If that solar system has a planet the same size as Earth orbiting at a distance of 1 AU , what is the orbital period of the planet? (Hint: The calculations for this problem are so simple that you will not need a calculator.) | 6 months |
The animation shows a collapsing cloud of interstellar gas. As the cloud collapses, the force of gravity drawing the cloud inward __________ because __________. | gradually becomes stronger the strength of gravity follows an inverse square law with distance |
According to the law of universal gravitation, what would happen to Earth if the Sun were somehow replaced by a black hole of the same mass? | Earth's orbit would not change. |
If the Moon were closer to Earth, high tides would: | be higher than they are now. |