PHYSICS LAB

   

Experiment 2

Collision — Conservation of Momentum and Kinetic Energy

Procedure:

1. Go to

http://www.walter-fendt.de/ph14e/collision.htm

.

2. Read the instruction.

3. If the Elastic Collision button is not checked, then click on.

4. Click reset – then change the values of M1, M2, V1b , and V2b to the values given

in Table 1.

5. Click Start, observe the collision and record the velocities of the two wagons after

after the collision (the two velocities will be displayed at the lower left portion.)

6. Calculate KE1b, KE1a, KE2a, KE2b, KE2b, P1a, P2a, P1b, and P2b.

7. Complete table 1

Table 1

M1 M2 V1b V2b V1a V2a KE1b KE2b KE1a KE2a P1b P2b P1a P2a

(kg) (kg) m/s m/s m/s m/s J J J J * * * *

1 1 0.3 0

1 1 0.5 -0.5

0.8 1 0.4 0.2

M1 = mass of Wagon 1

M2 – mass of wagon 2

V1b = Velocity of Wagon 1 before collision, V2a = Velocity of Wagon 2 after collision

V2b = Velocity of Wagon 2 before collision, V1a = Velocity of Wagon 1 after collision

KE1b = kinetic energy of Wagon 1 before collision

KE1a = kinetic energy of Wagon 1 after collision

KE2a = kinetic energy of Wagon 2 after collision

KE2b = kinetic energy of Wagon 2 before collision

KE2b P2b = Momentum of Wagon 2 before collision

P1a = Momentum of Wagon 1 after collision

P2a = Momentum of Wagon 2 after collision

P1b = Momentum of Wagon 1 before collision

* = kg.m/s

Questions:

a. How much kinetic energy is lost in the collision?

b. How much momentum was lost in the collision?

c. Was momentum conserved? Explain.

d. Was kinetic energy conserved? Explain.

1. Click the inelastic button.

2. Click reset – then change the values of M1, M2, V1b , and V2b to the values given

in Table 2.

3. Click Start, observe the collision and record the velocities of the two wagons after

after the collision (the two velocities will be displayed at the lower left portion.)

4. Calculate KE1b, KE1a, KE2a, KE2b, KE2b, P1a, P2a, P1b, and P2b.

5. Complete table 2.

Table 2

M1 M2 V1b V2b V1a V2a KE1b KE2b KE1a KE2a P1b P2b P1a P2a

(kg) (kg) m/s m/s m/s m/s J J J J * * * *

1 0.5 0.3 0

1 0.5 0.5 -0.3

0.8 1 0.4 0.2
Questions:
a. How much kinetic energy is lost in the collision?
b. How much momentum was lost in the collision?
c. Was momentum conserved? Explain.

d. Was kinetic energy conserved? Explain

Submit your formal lab report as outlined in the lab syllabus.