Friction & Gravity

What are the two important forces in moving objects?

• friction and fire

• gravity and weight

• gravity and friction

• fire and water

What do you call the invisible force that pulls everything towards the center of the Earth.

• water

• friction

• magnet

• gravity

What do you call the invisible force formed when you rub two objects together.

• heat

• magnet

• fire

• friction

Which force enables you to walk from your house to the marketplace?

• friction

• gravity

• magnet

• street

Which force makes two pieces of wood to make fire?

• gravity

• lighter

• matchstick

• friction

How do you lessen the friction of two objects?

• rub slowly

• put oil

• put glue

• rub faster

Which energy does friction produce?

• heat and light

• heat and sound

• light and sound

• sound and heat

Where does gravity pull everything?

• center of the sun

• edge of the earth

• edge of the universe

• center of the earth

Why do you need wheels to pull objects?

• to lessen friction

• to lessen gravity

• to lessen weight

Which of the following surfaces has less friction?

• rough floor

• grass

• cement

• tiled floor