Newton’s Cradle
Athira AP
A Newton’s cradle is also called a Newton’s pendulum, Newton’s rocker or a ball clicker. It was named after the great physicist Sir Isaac Newton and was designed by Edme Mariotte. Newton’s cradle demonstrates the principles of conservation of energy and conservation of momentum with swinging spheres.
Newton’s cradle consists of several balls that are hung in a line from two strips that are parallel to the line of the balls. These strips are mounted to a heavy base for stability. Here the balls could only move in one plane, parallel to the strips. All the balls are exactly of the same size, weight, mass and density. The balls can either be big or small but should be of exactly the same size and density. Newton’s cradle balls are commonly made of materials like Stainless steel because it has high elasticity, uniform density and are relatively cheap.
When one ball is released from one end, exactly one ball leaves from the other side and the process repeats. This is because as soon as the released ball hits the first ball, the momentum and energy transfer happen only between those two balls, that is the second ball gains the velocity of the first ball and the first ball comes to rest. This process is repeated between the second and the third ball and so on and finally, the ball leaves from the other end. Now, the same process is repeated from the other side resulting in an interesting pattern of motion and eventually it stops. This is because of air resistance, movement of the string that gets turned into heat and so the balls heat up slightly and they lose a lot of their energy to sound.
Check your knowledge
Air resistance, movement of the string that gets turned into heat and so the balls heat up slightly and they lose a lot of their energy to sound.
Yes, Newton’s cradle demonstrates the principles of conservation of energy and conservation of momentum with swinging spheres.
Newton’s cradle balls are commonly made of materials like Stainless steel because it has high elasticity, uniform density and are relatively cheap.
