Physics Gravity and Gravitation 1

Question 1

According to Newton's Law of Universal Gravitation, the force between two objects is:

Accepted Answer

Directly proportional to the product of their masses and inversely proportional to the square of the distance

Answer

Newton's Law states F = Gm₁m₂/r², so force increases with mass product and decreases with the square of distance.

Question 2

If the distance between two objects doubles, the gravitational force between them:

Accepted Answer

Decreases to one-quarter of the original

Answer

Since F ∝ 1/r², doubling the distance gives F ∝ 1/(2r)² = 1/(4r²), reducing the force to one-quarter.

Question 3

The acceleration due to gravity at Earth's surface is approximately:

Accepted Answer

9.8 m/s²

Answer

Earth's surface gravitational acceleration g ≈ 9.8 m/s², a fundamental constant used in weight and free-fall calculations.

Question 4

Which of the following best describes gravitational potential energy near Earth's surface?

Accepted Answer

PE = mgh, increasing as height increases

Answer

Gravitational PE near Earth's surface is PE = mgh, which increases as an object is lifted to a greater height.

Question 5

Kepler's First Law states that planetary orbits are:

Accepted Answer

Ellipses with the Sun at one focus

Answer

Kepler's First Law states that planets travel in elliptical orbits with the Sun located at one of the two foci.

Physics Practice Test