Physics Quiz on Gravitation and Fields

What does Newton's law of gravitation imply about the force between two point masses?

• The force is directly proportional to the distance between them.

• The force is inversely proportional to the distance between them.

• The force is directly proportional to the square of the distance between them.

• The force is inversely proportional to the square of the distance between them.

What happens to the gravitational force between two masses if the distance between them is tripled?

• The force decreases by a factor of 3.

• The force decreases by a factor of 9.

• The force increases by a factor of 9.

• The force remains unchanged.

According to Kepler's third law, the square of the orbital period of a planet is proportional to which power of the semi-major axis of its orbit?

• The cube

• The square

• The fourth power

• The first power

What is the gravitational field strength at a point where a small point mass experiences a gravitational force?

• The force divided by the square of the mass of the point

• The force multiplied by the square of the mass of the point

• The force divided by the mass of the point

• The force multiplied by the mass of the point

What is the effect of a frictional force (viscous drag) on a satellite's orbit radius and speed?

• Increases both radius and speed

• Decreases both radius and speed

• Decreases radius but increases speed

• Increases radius but decreases speed

What is the gravitational field strength on the surface of a planet if a satellite orbits the planet at a height equal to the planet's radius?

• It remains the same as at the surface.

• It is halved.

• It is one-fourth.

• It is doubled.

What does the gravitational field strength around a point or spherical mass indicate?

• It is uniform and constant.

• It decreases as we move away from the mass.

• It increases as we move away from the mass.

• It remains constant regardless of distance.

If the distance between two bodies is doubled, what happens to the gravitational force between them?

• It quadruples.

• It is halved.

• It is quartered.

• It doubles.

What is the acceleration of free fall on a planet 10 times as massive as Earth and with a radius 20 times as large?

• 250 m/s²

• 2.5 m/s²

• 0.25 m/s²

• 25 m/s²

What is the ratio of the gravitational field strength at a point halfway between two equal spherical masses?

• 0

• 1

• It cannot be determined from the given information.

• 2