Science & Engineering

What is a force?

A force is a push or a pull on something. It can cause an object to change its speed, direction or shape. When you push a trolley it increases its speed. The force can also cause the trolley to change direction. You use force to twist open the lid of a jar. This is called turning force or torque. If you apply a force to a soft ball, by squeezing it, you change the shape of the ball.

What is a lever?

The lever is considered one of the 6 basic simple machines. A lever can help us to lift heavy loads with less effort.

A lever can be simply a stick or bar which you push or pull against a fulcrum (or pivot) in order to move something.

What are levers used for?

A lever lets you do a lot of easy work instead of doing a little bit of hard work. If you're trying to lift a heavy rock 50cm off the ground, you might not be able to lift it at all. But if you have a lever - a long stick - you can get a mechanical advantage. You can push the lever down pretty easily, but you might have to move it down 200cm in order to lift the rock 50cm. You've done a lot of easy work (pushing down for 200cm) instead of a little hard work (pulling up for 50cm). It's the same amount of work, in the end, but spread out more.

Effort, Load and Fulcrum (or Pivot)

A pivot is a central point on which the lever rests and turns. This can also be called a fulcrum.

The load is the object which needs to be moved.

The effort is the force that you must use in order to move the load. The following picture shows that the rock is the load, the person is applying force and this is the effort. Where is the fulcrum (or pivot) in this picture?

Levers in everyday life

Using a screwdriver to open a tin of paint.

Using a hammer to pull out a nail.

Playing on a see saw.

Using a brick separator to take lego bricks apart.

Using a bottle opener to open a bottle

Using a scissors to cut something.

Using a wheelbarrow

Using a nutcracker

Using a tweezers

There are 3 classes of lever

1st Class Lever

The first class lever has the fulcrum between the load and the effort. (fulcrum in the middle)

The 2nd Class Lever

The second class lever has the load between the effort and the fulcrum. (load in the middle)

The 3rd Class Lever

The third class lever has the effort between the load and the pivot. (effort in the middle)

Keep an eye out over the next few days! Can you spot any levers in your everyday life?

Next Week at Designer Minds Club! You will learn how levers work using LEGO educations kits.

Next week you will work …

In a group of 2.

You are doing this because… 1. Understanding how things work gives you the skills to be able to fix things and invent new ways of doing things! 2. Exploring engineering using LEGO is fun! 3. The world needs engineers to help solve problems, create useful things and make the world a better place. 4. Engineering helps you to connect real world items to science and Maths. It helps to show you how Maths and Science are relevant to your life. 5. There are many types of engineers, who design many different things. Would you like to be an engineer?

Explore at Home!

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Simple Machines https://www.youtube.com/watch?v=yOxc3Bmr60A