Objective: observe a perfect elastic collision between two objects.

1. Take the mass of the tennis balls being used

mass of ball 1: 0.0056 kg mass of ball 2: 0.0056 kg

1. Line up one ball so that it is stationary and another ball that will move towards it in a straight line. One person will be responsible for recording the time and distance it travels in order to calculate its initial speed. (5 K)

2. After impact, calculate the speed of both balls using the same method, and record (10 K)

3. Perform calculations for what the theoretical final velocities of the balls should be and compare. (10 T)

4. Calculate the percentage deviation between the calculated and the measured final speeds (5 T)

Attempt	Initial Distance (m)	Initial time (s)	Initial velocity of ball 1 (m/s)	Initial velocity of ball 2 (m/s)
1	0.87	1.37	0.635	0
2	0.87	1.82	0.478	0
3	0.87	2.69	0.323	0
4	0.87	2.83	0.307	0
5	0.87	1.41	0.617	0

Attempt	Final distance of ball 1 (m)	Final time of ball 1 (s)	Final velocity of ball 1 (m/s)	Final distance of ball 2 (m)	Final time of ball 2 (s)	Final velocity of ball 2 (m/s)
1	0.05	1.06	0.0471	0.33	2.40	0.138
2	0.095	1.00	0.095	0.255	2.46	0.104
3	0.11	0.79	0.139	0.24	1.9	0.126
4	0.16	0.73	0.219	0.47	2.81	0.167
5	0.09	0.86	0.105	0.32	2.03	0.158

Attempt	Calculated final velocity of ball 1 (m/s)	Calculated final velocity of ball 2 (m/s)	Percentage Error of ball 1	Percentage Error of ball 2
1	0	0.635	Undefined	78.3 %
2	0	0.478	Undefined	78.2 %
3	0	0.323	Undefined	61.0 %
4	0	0.307	Undefined	45.6 %
5	0	0.617	Undefined	74.4 %

Questions

1. What may have been the causes behind the % errors in the calculated vs measured final velocities? (5 A)

2. Why might it be possible to perform the experiment without needing to measure the mass of the two balls? Even if it is true, why is it important to still perform the measurements regardless? (5 A)

3. How would the knowledge obtained in this experiment be applicable in real life situations? (5 A)

4. In this experiment, identify 4 sources of error in the performing of the lab that need to be accounted for, and provide a solution for how these errors can be fixed. (10 C)

I have to answer the 4 questions above!