Weight, apparent weight, and weightlessness | AP Physics | Khan Academy

What is the scientific definition of weight?

• The amount of matter in an object.

• The gravitational force exerted by any body on another body.

• The gravitational force exerted by a massive body on a relatively small nearby body.

• The resistance of an object to acceleration.

When considering the gravitational interaction between the Earth and the Moon, why is the force exerted by the Earth on the Moon typically NOT referred to as the Moon's "weight"?

• The Moon is too far away from Earth for gravity to have a significant effect.

• Both the Earth and the Moon are considered massive astronomical bodies in this context.

• The Moon has no atmosphere, which prevents the concept of weight from applying.

• Weight only applies to objects on the surface of a planet.

Which of the following expressions correctly represents the magnitude of the gravitational force (weight) on an object of mass 'm' near a massive body, where 'g' is the gravitational field strength at that location?

• Fg = m/g

• Fg = m * g

• Fg = G * m * M / r

• Fg = G * M / r^2

What does a typical weighing scale primarily measure when an object is placed on it?

• The object's mass.

• The gravitational force acting on the object.

• The normal force exerted by the scale on the object.

• The object's density.

When an object is at rest on a horizontal surface, how does the normal force exerted by the surface compare to the object's gravitational force?

• The normal force is greater than the gravitational force.

• The normal force is less than the gravitational force.

• The normal force is equal to the gravitational force.

• The normal force is zero.

A person standing on a weighing scale inside an elevator that is accelerating upwards will observe their apparent weight to be:

• Less than their actual weight.

• Greater than their actual weight.

• Equal to their actual weight.

• Zero.

If an elevator is accelerating downwards, how does the normal force acting on a person inside compare to their gravitational force?

• The normal force is greater than the gravitational force.

• The normal force is equal to the gravitational force.

• The normal force is less than the gravitational force.

• The normal force is zero.

Which of the following situations would result in a sensation of weightlessness for a person inside an elevator?

• The elevator is accelerating upwards at 9.8 m/s².

• The elevator is moving downwards at a constant speed.

• The elevator's cable breaks, causing it to free fall.

• The elevator is accelerating downwards at 5 m/s².