# Forces/Pressure

Get Started. It's Free Forces/Pressure ## 1. How can we measure a force?

### 1.1. Forces are measured with force-meters. Spring balances are force-meters. -Extension spring balances -Compression spring balances

1.1.1. 1) In a compression spring balance, the spring is compressed when a force acts on it. 2) In a compression spring balance, the spring is compressed when a force acts on it.

## 3. What is a force?

### 3.1. A force is a push or pull. Whenever we push or pull something, we are said to exert a force.

3.1.1. Lifting/ bending/ stretching/twisting/ squeezing involves pushes and pulls

## 5. How can we decrease pressure?

### 5.1. To reduce pressure, increase the area of the object to exert lesser pressure.

5.1.1. for example, a camel has large feet so the pressure exerted will be reduced and the camel will not sink into the sand.

## 6. How to calculate pressure?

### 6.1. To calculate pressure we use the formula : force/Area

6.1.1. The unit of pressure is N/m2 also known as pascal. Pascal is the SI unit for pressure. For example a hippopotamus weighs 40000N it stands on one foot on the ground what is the pressure? 40000N = 40/cm2 1000cm2

## 7. How can we increase pressure?

### 7.1. to increase pressure you reduce the area of the object to exert more pressure.

7.1.1. for example, a sharp knife will exert more pressure than a blunt knife.

## 10. Different type of forces

### 10.1. Frictional force

10.1.1. Magnetic force

10.1.1.1. Gravitational force

## 11. Effects of the different forces

### 11.1. Frictional force: Also called friction Occurs when two moving surfaces are in contact Effects: Slows down and/or stops a moving object Produces heat

11.1.1. Magnetic force:Force exerted by a magnet on a magnetic material (e.g. iron and steel) or another magnet. Forces between magnets: Like poles repel: Magnets push away from one another Unlike poles attract: Magnets pull towards each other

11.1.1.1. Gravitational foce: Also called gravity Exists between any two objects This is the force that causes all objects to be attracted to the Earth.