- A force is a push or a pull acting upon an object
- When an object is pushed or pulled, a forced is exerted on the object
- We can only see the effets of forces
Effects of forces :
- A force can
- change the shape and size of an object
- move a stationary object
- stop a moving object
- change the position of a moving object
- change the direction of a moving object
Different type of force:
Electrostatic Force
- Electrostatic force is a force which exists between static electrical charges
- Two objects which opposite charges attract each other
- Two objects with the same charges repel each other
- When a plastic rules is rubbed with a cloth, it can attract small pieces of paper that are not charged
Gravitional Force
- Gravitional force is a force that pulls all object towards the centre of the earth
- Gravity makes all thing fall to the ground
- Gravity is stronger at the poles than at the equator
- The weight of an object is the force of gravity pulling that object down
Frictional Force
- Frictional force is the force acting on the surfacee of an object when it moves against the surface of another object
- Fricton is produced when two surface rub against each other
- Frictional force acts in the opposite direction to movement
- Friction can (a)stop a moving object (b)prevent an object from moving
- The magnitude of friction between two surfaces that are in contact increase when the (a)surface is rougher (b)object is heavier
- Frictional force does not depend on the surface area in contact
Magnetic Force
- Magnetic force is a force that exists in a magnetic field
- A magnet can exert force on the another magnet or on icon and steel
- Unlike poles of magnet attract each other, while like poles repel each other
references : whizz science
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