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Two characters pushing a bear in a box
Image caption,
Forces are pushes or pulls. They are measured in newtons.

Forces

Forces are just pushes and pulls in a particular direction.

Forces are shown by arrows in diagrams. The direction of the arrow shows the direction in which the force is acting. The bigger the arrow, the bigger the force.

Balanced forces

If two forces are balanced, it means the forces are the same size but are acting in opposite directions.

If two balanced forces are acting on an object, that object will not change its motion. If it is still, the object will stay still or if it is moving, it will continue moving in the same direction and at the same speed.

Unbalanced forces

When two forces acting on an object are not equal in size, we say that they are unbalanced forces. Unbalanced forces do change the way something is moving.

They can make objects start to move, speed up, slow down or change direction.

Two characters pushing a bear in a box
Image caption,
Forces are pushes or pulls. They are measured in newtons.

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