Page 143 - Active Science 5 Ebook and Activity

Electrostatic Force
The opposing force between two charged particles at a distance is called electrostatic

force. Let’s perform an activity to understand this force clearly.

Activity 13.1

Aim : To learn about electrostatic force.

Materials Required: Balloon, hair

Procedure : • Take a balloon.

• Rub the balloon against your hair.
Observation : You will find your hair stand up even when
the balloon is not near you.

Conclusion : Each hair is positively charged and the balloon gets negatively
charged after rubbing. Therefore, they attract each other.

Magnetic Force

Magnetic force is the power which pulls different
materials towards a magnet. It attracts only some types
of metals. Materials such as glass, wood and plastic are
not attracted. If a material gets attracted towards a
magnet, then it is called a magnetic material. There
are two poles of a magnet. One is the North Pole and the Magnetic force
other is the South Pole. If we bring them close, they oppose each other. But if we bring

the same poles closer, they will repel.

Frictional Force

Frictional force acts in the opposite direction to stop a moving object in the direction of
motion. It acts upon two things – one stationary and the other moving. Rough surfaces
have more friction than the smoother ones.

Suppose you push a notebook on the table, the book will move. The force of pushing

moves the book. As the notebook slides across the table, it slows down at a distance and
the motion of the book stops. The opposition of motion is called friction.

Advantages of Friction

a. Friction help us in walking on the floor.
When you walk on the floor, it holds

your slippers to the ground and allows
you to walk.

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