APPARATUS Set of weights, electronic balance, trolley, ticker-tape timer and tape. DIAGRAM PROCEDURE Set up the apparatus as shown in the diagram. The track is tilted slightly so that the trolleys will move at constant velocity when given an initial push. Note the mass of both trolleys to begin with. Both trolleys are initially at rest. Trolley one is given an initial push such that it moves at constant velocity until it collides with Trolley two whereupon they will join together (because of the velcro) and move off as one combined mass Use the ticker-tape to calculate the velocity of Trolley one before the collision and the velocity of the combined mass after the collision. Repeat the experiment a few times, each time adding masses from one trolley to the other . Record the results in the table and for each run calculate the total momentum before and after the collision. RESULTS AND CALCULATIONS: MOMENTUM BEFORE MOMENTUM AFTER Total Before Total After m1 u1 m1u1 m2u2 m1u1+m2u2 m2 (m1 + v3 (m1 + m2)v3 m2) CONCLUSION After completing the experiment we found that in each case the total momentum before the collision equalled the total momentum after the collision (within the limits of experimental error), in agreement with the theory. SOURCES OF ERROR / PRECAUTIONS Ensure that the runway in smooth, free of dust, and does not sag in the middle. Ensure that the runway is tilted just enough for the trolley to roll at constant speed. Notes on the Conservation of Momentum experiment If using the linear air-track In this case friction an issue and therefore the air-tack should be level. isn’t To see if the track is level check that the trolley drift toward either end. doesn’t Block the ten pairs of air holes nearest the buffer end of the track with cellotape. This part of the track will now act as a brake on the vehicle. Occasionally check the air holes on the linear air-track with a pin, to clear any blockages due to grit or dust. If using the traditional ramp and ticker-tape timer The track is tilted slightly (as in the diagram above) so that the trolleys will move at constant velocity when given an initial push.
APPARATUS Set of weights, electronic balance, trolley, ticker-tape timer and tape. DIAGRAM PROCEDURE Set up the apparatus as shown in the diagram. The track is tilted slightly so that the trolleys will move at constant velocity when given an initial push. Note the mass of both trolleys to begin with. Both trolleys are initially at rest. Trolley one is given an initial push such that it moves at constant velocity until it collides with Trolley two whereupon they will join together (because of the velcro) and move off as one combined mass Use the ticker-tape to calculate the velocity of Trolley one before the collision and the velocity of the combined mass after the collision. Repeat the experiment a few times, each time adding masses from one trolley to the other . Record the results in the table and for each run calculate the total momentum before and after the collision. RESULTS AND CALCULATIONS: MOMENTUM BEFORE MOMENTUM AFTER Total Before Total After m1 u1 m1u1 m2u2 m1u1+m2u2 m2 (m1 + m2) v3 (m1 + m2)v3 CONCLUSION After completing the experiment we found that in each case the total momentum before the collision equalled the total momentum after the collision (within the limits of experimental error), in agreement with the theory. SOURCES OF ERROR / PRECAUTIONS Ensure that the runway in smooth, free of dust, and does not sag in the middle. Ensure that the runway is tilted just enough for the trolley to roll at constant speed. Notes on the Conservation of Momentum experiment If using the linear air-track In this case friction isn’t an issue and therefore the air-tack should be level. To see if the track is level check that the trolley doesn’t drift toward either end. Block the ten pairs of air holes nearest the buffer end of the track with cellotape. This part of the track will now act as a brake on the vehicle. Occasionally check the air holes on the linear air-track with a pin, to clear any blockages due to grit or dust. If using the traditional ramp and ticker-tape timer The track is tilted slightly (as in the diagram above) so that the trolleys will move at constant velocity when given an initial push.