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3rd Grade: Science : Force: muscular, gravitational, magnetic, frictional

Force  :

Force is needed to pull or push something. Eg a bull pull a cart because it applies force. Thus , force can make things speed up, slow down, or change direction.

Types of force:
Muscular force
Gravitational force
Magnetic force
Frictional force


Muscular force : what happens when you pedal your bicycle? The cycle moves. Your muscles apply force to the pedals.
Force applied by muscles is called muscular force.

Gravitational force : when we throw a ball up in the air, it slows down and then falls to the ground. Fruits from a tree always fall to the ground . This is because the Earth pull everything towards its centre. 
The Force of the Earth that pulls everything towards itself is called gravitational force or gravity.

Magnetic force: the magnet pulls iron objects towards itself , which then stick to the magnet . 
This pull of the magnet is called magnetic force.

Frictional force : a bicycle has hand brakes on both wheels. When brakes are applied, they rub against the wheels. Friction between the brakes and the wheels slows down the bicycle. Sometimes to stop, you place your foot on the ground. The friction between the foot and the ground brings tthe bicycle to a halt.
Friçtion is the Force that stops or slow down a moving object.

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