# Force & Pressure

Get Started. It's Free
Force & Pressure

## 4. Kinds of forces

### 4.1. Gravitational Force

4.1.1. Gravitational Force is a force that pulls objects towards the Earth

4.1.2. It causes objects to have weight

4.1.3. The stronger the gravitational pull, the greater the weight of an object.

4.1.4. Weight=Mass*Gravitational Force

4.1.5. Gravitational Force of the Earth is 10N/kg.

### 4.2. Magnetic Force

4.2.1. Force between magnets.

4.2.2. Have two different poles North(S) & South(S).

4.2.3. Like poles repel & Unlike poles attract.

### 4.3. Frictional Force

4.3.1. A Force that exists when two objects are in contact.

4.3.2. Friction slows down the motion of object.

4.3.3. Ball bearings, wheels & applying lubricant helps reduce friction.

4.3.4. Friction can be a nuisance.

4.3.4.1. Eg. It causes wear-and-tear in an object or converts useful energy to heat which is unnecessary.

4.3.5. However,Friction is useful.

4.3.5.1. Eg. It prevents us from falling when we walk or run.