Balancing Forces

Science · Chapter 3 · Test Wednesday, September 15

Everything you need to know

Five vocabulary words and two big ideas. Read this first, then play the games.

Two kinds of forces

Touching force
  • The two objects are touching.
  • Kicking a ball
  • Pushing a tire
  • A cat pushing a vase off a shelf
  • Pulling a wagon
Non-touching force
  • The two objects are not touching.
  • Gravity is a non-touching force
  • An apple falling from a tree
  • A magnet pulling a paper clip from far away
  • A ball dropping after you let go

How to answer the picture questions

Two cars are on ramps. Car A is at the bottom. Car B is at the top. Which car will move because of gravity?
Car B will move because gravity is a pulling force, so car B will be pulled down the ramp toward Earth. Car A is already at the bottom of the ramp, so gravity will not pull it down any further.
A cat pushes a flower vase off a shelf. What will happen to the vase?
The vase will fall to the floor because gravity is pulling it down toward Earth. Once the cat pushes the vase off the shelf, there is nothing left to stop gravity from pulling it down.
A boy pushes a tire to the left. Which two forces are being exerted on the tire?
A push and a touching force. The arrow points the same way the boy is pushing — to the left.
Why does an apple fall from a tree? Use science words.
The apple falls from the tree because of the force of gravity. Gravity attracts objects toward Earth. Forces act between two objects. Earth is the object that exerted a force on the apple. Gravity is a non-touching force, so it acts without Earth touching the apple.