Newton's Law of Universal Gravitation(NLUG)

What two factors effect the magnitude of the force of gravity between objects are...

• mass and distance

• mass and matter

• distance and weight

• weight and mass

Answer explanation

The force of gravity between two objects is determined by their mass and the distance between them. Greater mass increases gravitational force, while greater distance decreases it, making 'mass and distance' the correct factors.

The gravitational pull is __________ proportional to the mass of each object.

• conversely

• directly

• phonetically

• inversely

Answer explanation

The gravitational pull between two objects is directly proportional to the mass of each object, meaning that as the mass increases, the gravitational force also increases.

The space shuttle is orbiting the Earth clockwise. Which vector shows the direction of the gravitational force acting on the shuttle?

• a

• b

• c

• d

Answer explanation

The gravitational force always acts towards the center of the Earth. Since the shuttle is orbiting clockwise, the vector that points downward towards the Earth (choice a) correctly represents the direction of this force.

Complete the following statement: The farther away two planets are the _______ the gravitational force between them.

• more

• same

• dosen't matter

• less

Answer explanation

The gravitational force between two planets decreases as the distance between them increases, according to Newton's law of universal gravitation. Therefore, the correct completion is 'less'.

Newton's Law of Universal Gravitation affects

• All objects with mass in the known universe

• All objects and empty space in the known universe

• All objects in motion.

• All objects traveling in a circular path.

Answer explanation

Newton's Law of Universal Gravitation applies to all objects with mass, meaning it affects every mass in the universe, not just those in motion or in circular paths. Thus, the correct choice is 'All objects with mass in the known universe'.

A rocket moves away from the surface of Earth. As the distance r from the center of the planet increases, what happens to the force of gravity on the rocket?

• The force doesn’t change

• The force increases directly proportional to 𝑟²

• The force decreases inversely proportional to 1/𝑟²

• The force becomes zero after the rocket loses the contact with Earth

Answer explanation

As the rocket moves away from Earth, the gravitational force decreases according to the inverse square law, meaning it is inversely proportional to 1/r². Thus, the correct choice is that the force decreases inversely proportional to 1/r².

How are mass and weight different?

• Mass is the amount of matter in an object; Weight is the amount of gravitational force acting on the object

• Mass is the amount of gravitational force acting on an object; Weight is the amount of matter in an object

• Mass is a thing;Weight is a place

• Mass is an animal;weight is a human

Answer explanation

Mass refers to the quantity of matter in an object, while weight is the force exerted by gravity on that mass. Thus, the correct choice clearly distinguishes between these two fundamental concepts.

What type of interaction is a gravitational force? 

• Attractive

• Repulsive

• Attractive and repulsive

• No interaction exists. 

Answer explanation

Gravitational force is an attractive interaction, meaning it pulls objects toward each other. Unlike repulsive forces, which push objects apart, gravity always acts to attract masses, confirming that the correct choice is 'Attractive'.

If Earth's mass was cut in half, what would happen to your mass?

• increase because gravitational force increases

• decrease because gravitational force decreases

• decrease because gravitational force increases

• nothing, mass is not affected by gravitational force

Answer explanation

Your mass remains unchanged because mass is an intrinsic property of matter, independent of gravitational force. Even if Earth's mass is halved, your mass does not change.

What happens to gravitational force between two object if both masses are doubled?

• doubles

• half as big

• 4x bigger

• 4x smaller

Answer explanation

Gravitational force is proportional to the product of the masses. If both masses are doubled, the force becomes 2m * 2m = 4m^2, which is 4 times bigger than the original force. Thus, the correct answer is 4x bigger.