Quiz on Gravity, Friction, Energy, and Machines

Which factor causes objects to fall toward the Earth when dropped?

• Wind

• Gravity

• Friction

• Magnetism

What happens to the gravitational force when an object’s mass increases?

• It becomes weaker

• It stays the same

• It becomes stronger

• It disappears

Which object would feel the strongest pull of gravity?

• A pencil case

• A schoolbag

• A cellphone

• A paperclip

Which of the following best describes gravity?

• A push from the ground

• A force that pulls objects upward

• A force that pulls objects toward each other

• A force that causes friction

Which planet would have the strongest gravitational force?

• Mars

• Earth

• Jupiter

• Mercury

An object has a mass of 6 kg. What is its weight on Earth? (g = 9.8 m/s²)

• 58.8 N

• 60 N

• 45 N

• 48.8 N

On the Moon, a rock has a mass of 10 kg. What is its weight if the Moon’s gravity is 1.6 m/s²?

• 10 N

• 16 N

• 98 N

• 6.25 N

What is the effect of friction on moving objects?

• It speeds them up

• It changes their shape

• It slows them down

• It makes them fly

Which surface would likely cause the most friction?

• Ice

• Carpet

• Glass

• Metal

Which situation shows the harmful effect of friction?

• Brakes stopping a car

• Shoes gripping the floor

• Worn-out tires

• Walking without slipping