Coefficient of Restitution (Cor) of 3 Balls
How does the COR affect different types of sports balls bounce on different types of surfaces?
AIM the aim of this experiment is to find out how the COR (coefficient of restitution) of 3 balls (tennis ball, snooker ball and ping pong ball).
FORMULA USED FOR COR
GPE (after) = KE (after)
GPE (before) = KE (before)
mxgxHr = ½ x mx Vout² mxgxHd ½ x m Vin²
Hr = Vout²
Hd Vin²
APPARATUS
meter stick,
tennis ball,
ping pong ball,
snooker ball,
surfaces; wood and carpet
METHOD - I will firstly organize all the apparatus that are needed for this experiment.
1. I will make 3 tables for my results to be recorded in.
2. Then I will get my partner to hold the meter stick firmly with one hand.
3. In the other hand of my partner, the first ball will be held.
4. My partner will drop the ball from a height of 100cm.
5. I will keep at eye level and watch closely
6. I will record the height, to the nearest cm, of the highest point that the ball bounces to.
7. I will repeat this method ten times on wood, and then ten times on carpet.
8. I will then bring into play the two other balls, and do the same as I have done with the first ball.
PREDICTION I predict that the tennis ball will bounce higher on wood than the other two balls. Reason being that the tennis ball is lighter than the snooker ball and requires less force. The material used is also a factor that will help it bounce higher than the ping pong ball.
RISK ASSESMENT Item Risk Reduce hazard Implementation
All balls used
(football, tennis ball, ping pong ball) Some balls may be heavy and hurt someone Be sure to keep a safe distance When I let go of the ball, I made sure I moved back.
There were no other significant hazards.
DIAGRAM OF EXPERMIMENT-
Results -
Tennis Ball -
On carpet (cm) On wood (cm)
1st bounce 45 47
2nd bounce 44 55
3rd bounce 43 56
4th bounce 45 45
5th bounce 43 52
6th bounce
AIM the aim of this experiment is to find out how the COR (coefficient of restitution) of 3 balls (tennis ball, snooker ball and ping pong ball).
FORMULA USED FOR COR
GPE (after) = KE (after)
GPE (before) = KE (before)
mxgxHr = ½ x mx Vout² mxgxHd ½ x m Vin²
Hr = Vout²
Hd Vin²
APPARATUS
meter stick,
tennis ball,
ping pong ball,
snooker ball,
surfaces; wood and carpet
METHOD - I will firstly organize all the apparatus that are needed for this experiment.
1. I will make 3 tables for my results to be recorded in.
2. Then I will get my partner to hold the meter stick firmly with one hand.
3. In the other hand of my partner, the first ball will be held.
4. My partner will drop the ball from a height of 100cm.
5. I will keep at eye level and watch closely
6. I will record the height, to the nearest cm, of the highest point that the ball bounces to.
7. I will repeat this method ten times on wood, and then ten times on carpet.
8. I will then bring into play the two other balls, and do the same as I have done with the first ball.
PREDICTION I predict that the tennis ball will bounce higher on wood than the other two balls. Reason being that the tennis ball is lighter than the snooker ball and requires less force. The material used is also a factor that will help it bounce higher than the ping pong ball.
RISK ASSESMENT Item Risk Reduce hazard Implementation
All balls used
(football, tennis ball, ping pong ball) Some balls may be heavy and hurt someone Be sure to keep a safe distance When I let go of the ball, I made sure I moved back.
There were no other significant hazards.
DIAGRAM OF EXPERMIMENT-
Results -
Tennis Ball -
On carpet (cm) On wood (cm)
1st bounce 45 47
2nd bounce 44 55
3rd bounce 43 56
4th bounce 45 45
5th bounce 43 52
6th bounce