Dynamics of a Bouncing Ball
Physics Internal Assessment
Research Question: Of plywood, glass, stainless steel, and a ceramic tile, which least affects the dynamics of a bouncing table tennis ball?
Background Information: Table tennis is a ball game that can be played on any reasonably sized, flat, elevated surface. As is the case in any ball game, a crucial criterion to base which material to be used as a playing surface is the bounce of the ball. For any ball game to be fair to both sides, the playing surface must be such that the ball bounces back to a height that is as close as possible to the original height. Moreover, it is desired that the bounce be predictable. No ball game would be fun if the bounce is too uneven as this prevents the timing and strategic thinking of the player.
Theory and Explanation: The coefficient of restitution of an object is a fractional value representing the ratio of velocities before and after an impact. The coefficient of restitution can be calculated using the following equation:
Cr = hH
Where:
* ‘Cr‘ is the coefficient of restitution, * ‘h’ is the rebound height of the ball, * ‘H’ is the height that the ball was initially dropped from.
This shows that the coefficient of restitution of a collision is the ratio of the square root of the rebound height (h) by the drop height (H).
The coefficient of restitution varies from object to object and also according to the material which the object is impacted on (in this case bounced on). The value for the coefficient of restitution always ranges from 0 to 1 because ‘h’ cannot be greater than ‘H’. If a collision is perfectly elastic, the coefficient of restitution will be 1 and if the collision is perfectly inelastic, it will be 0. However, it is not practically possible for a collision to be perfectly elastic as in a collision energy is lost as it is converted to sound, heat and to overcome friction, and air resistance.
The higher the coefficient of restitution of a collision, the
Research Question: Of plywood, glass, stainless steel, and a ceramic tile, which least affects the dynamics of a bouncing table tennis ball?
Background Information: Table tennis is a ball game that can be played on any reasonably sized, flat, elevated surface. As is the case in any ball game, a crucial criterion to base which material to be used as a playing surface is the bounce of the ball. For any ball game to be fair to both sides, the playing surface must be such that the ball bounces back to a height that is as close as possible to the original height. Moreover, it is desired that the bounce be predictable. No ball game would be fun if the bounce is too uneven as this prevents the timing and strategic thinking of the player.
Theory and Explanation: The coefficient of restitution of an object is a fractional value representing the ratio of velocities before and after an impact. The coefficient of restitution can be calculated using the following equation:
Cr = hH
Where:
* ‘Cr‘ is the coefficient of restitution, * ‘h’ is the rebound height of the ball, * ‘H’ is the height that the ball was initially dropped from.
This shows that the coefficient of restitution of a collision is the ratio of the square root of the rebound height (h) by the drop height (H).
The coefficient of restitution varies from object to object and also according to the material which the object is impacted on (in this case bounced on). The value for the coefficient of restitution always ranges from 0 to 1 because ‘h’ cannot be greater than ‘H’. If a collision is perfectly elastic, the coefficient of restitution will be 1 and if the collision is perfectly inelastic, it will be 0. However, it is not practically possible for a collision to be perfectly elastic as in a collision energy is lost as it is converted to sound, heat and to overcome friction, and air resistance.
The higher the coefficient of restitution of a collision, the