# Force and Motion

## Newtons laws.

Have you ever heard of sir Issac Newtons laws of force and motion? Well there are three simple laws. We use force and motion so we can move and do everyday things. For example when yo push a box you are putting force on the box so it can move.

## Newtons 1st Law

Newton's first law clearly states that any object at rest stay in rest and any object in motion stays in motion unless acted upon by an outside force.

## Newtons 2nd law

Newton's second law says that f=ma (Mass x acceleration = force) and the greater the force the greater the acceleration.

## Newtons 3rd Law.

Newton's third law says For every action there is an equal and opposite reaction.

## Simple Machines

Have you ever heard of a simple machine. Well there are six very different kinds simple machines. There are also compound machines that use various different simple machines into one. Let's see what kind of simple machines there are come on.

## Lever

A lever is a straight bar that pivots on a fulcrum.

An example of a lever is a seesaw. The bar sits in the middle of the fulcrum and when one person sits on it, it goes up and down.

## Pulley

A pulley is a rope wrapped around a wheel and you pull the rope.

An example of this simple macine is when you pull the rope on a window shade. When you pull each time pull the shade goes up.

## Screw

The next simple machine is a screw.

A screw is just an inclined plane wrapped around a cylinder.

An example of a screw is a scew. It has the inclined plane wrapped around a cylinder.

## Wheel and axle

A wheel and axle is the next simple machine.

A wheel and axle is just a bar with a wheel attached to it so they rotate together at the same speed.

An example of a wheel and axle is a ferrice wheel. It has the wheel that spins and the bar that rotates with the wheel.

## Wedge

The next simple machine we wil look at is a wedge.

A wedge is an object having one thick end and tapering to a thin edge that is driven between two objects to separate them.

An example of this machine is a door stopper. When the door stopper goes in between the door and the floor it becomes a wedge.

## Inclined plane

The last simple machine we will look at today is an inclined plane.

An inclined plane is a flat surface tilted at an angle with one end higher than the other end.

An example of an inclined plane is a slide. It has one end higher than the other.

## Compound Machines.

What are compound machines?

Compound machines are machines that uses two or more various machines to make one compound machines.

Let's take a look at a few compound machines.

## Wheelbarrow

A wheelbarrow is a compound machine because it uses different types of simple machines.

As you can see the picture below it shows the different simple machines on a wheelbarrow.

## Pencil sharpener

Another compound machine is a pencil sharpener.

A pencil sharpener has many different simple machines in one.

When you look at the picture below it will tell you the different simple machines.