6.5 Newton's universal law of gravitation  (Page 8/13)

Jupiter has a mass approximately 300 times greater than Earth's and a radius about 11 times greater. How will the gravitational acceleration at the surface of Jupiter compare to that at the surface of the Earth?

1. Greater
2. Less
3. About the same
4. Not enough information

Given Newton's universal law of gravitation (Equation 6.40), under what circumstances is the force due to gravity maximized?

In the formula $g=\frac{GM}{r^2}$ , what does G represent?

1. The acceleration due to gravity
2. A gravitational constant that is the same everywhere in the universe
3. A gravitational constant that is inversely proportional to the radius
4. The factor by which you multiply the inertial mass to obtain the gravitational mass

Saturn's moon Titan has a radius of 2.58 × 10 ⁶ m and a measured gravitational field of 1.35 m/s ² . What is its mass?

A recently discovered planet has a mass twice as great as Earth's and a radius twice as large as Earth's. What will be the approximate size of its gravitational field?

1. 19 m/s ²
2. 4.9 m/s ²
3. 2.5 m/s ²
4. 9.8 m/s ²

4. Earth is 1.5 × 10 ¹¹ m from the Sun. Mercury is 5.7 × 10 ¹⁰ m from the Sun. How does the gravitational field of the Sun on Mercury ( g _SM ) compare to the gravitational field of the Sun on Earth ( g _SE )?

Action at a distance, such as is the case for gravity, was once thought to be illogical and therefore untrue. What is the ultimate determinant of the truth in physics, and why was this action ultimately accepted?

Two friends are having a conversation. Anna says a satellite in orbit is in freefall because the satellite keeps falling toward Earth. Tom says a satellite in orbit is not in freefall because the acceleration due to gravity is not $\mathrm{9.80\; m}{\text{/s}}^2$ . Who do you agree with and why?

Draw a free body diagram for a satellite in an elliptical orbit showing why its speed increases as it approaches its parent body and decreases as it moves away.

Newton's laws of motion and gravity were among the first to convincingly demonstrate the underlying simplicity and unity in nature. Many other examples have since been discovered, and we now expect to find such underlying order in complex situations. Is there proof that such order will always be found in new explorations?