Mohr's circle

Have you ever played with a hula hoop? Mohr's circle is kind of like a hula hoop, but for stress.

Imagine you have a ball with you and you squeeze it very hard. When you do this, the ball will create stress inside it. Stress is like a force that pushes and pulls on the ball from all different directions. Sometimes the force is pushing on the ball, and sometimes it's pulling on the ball.

Now, take a piece of paper and draw a big circle on it. This is like your hula hoop. Next, draw a point in the middle of the circle. This is like the ball you squeezed.

Now, imagine all the different forces that are pushing and pulling on the ball and causing stress. You can put these forces in the circle you drew as arrows. Some arrows will be pointing up, and some will be pointing down. Some arrows will point left and some will point right.

The circle you drew with all the arrows in it is like Mohr's circle. It shows all the different stresses acting on the ball at the same time.

This can help engineers and scientists understand how much stress is on an object from different directions, and they can use it to design things like buildings and bridges to make sure they won't break under stress.

So, just like a hula hoop, Mohr's circle can help us understand how things move and react under stress.