Notes

fourth experiment collisions and conservation of linear momentum part 1 elastic collision first place the carbon paper and the data sheet before beginning the experiment you need to check whether the air table is inclined or not for this purpose place one of the pucks in the middle of the paper andpress on the p-switch set the air table parallel to the ground using its supports after that set the frequency in this experiment both of the parks will undergo uniform motion with constant velocity press on the p-switch while keeping the parks fixed the park should collide somewhere in the middle of the table launch them appropriately with a moderate velocity you may need a number of trials before recording the data first you need to determine where the collision took place the collision took place in this region it is necessary to determine the velocities of the pucks before and after the collision in order to observe conservation of linear momentum for this purpose first determine the velocities of the parks before the collision in order to determine the velocities and hence the momenta of the parks begin by determining the directions of motion choose three consecutive intervals near the collision region measure the distance between the zeroth and the third points calculate the time in which the park moves from the zeroth point to the third point calculate average velocity of the park using the formula average velocity equals to Delta x over delta T now repeat the procedure to calculate the velocity of the other park before the collision calculate total momentum before the collision momentum vector of an object equals to the product of its mass and velocity vector in this experiment the parks are identical so it is sufficient to calculate their resultant velocity vector for this purpose drove vectors representing the velocities of the parks using a scale and taking the directions of motion into consideration for instance that your scale be the distances used for calculating the velocities use parallelogram technique to calculate the resultant vector the resultant vector is now calculated now measure the length of the resultant vector calculate the magnitude of the resultant velocity by dividing this length with the time interval used for calculating the velocities repeat the procedure for post collision data and compare total momenta before and after the collision using the calculated velocities and the masses of the puckscalculate and compare total kinetic energies before and after the collision in the end examine the motion of the center of mass for this purpose first choose simultaneous points since the pucks are identical the center of mass is always the midpoint of these points using those points calculate thevelocity of the center of mass before and after the collision with these calculations you have tested the conservation of linear momentum and kinetic energy part 2 inelastic collision in this part of the experiment the pucks should stick together and move as a single object for this purpose back row bands will be wrapped around the pucks it is necessary to wrap the bands tightly after the collision the parks may begin rotating since you are not going to examine rotational motion you should prevent this rotation for that reason it may be necessary to make a number of trials before recording the data now you can analyze the data you are going to repeat the procedure of the first part motion of the center of mass will not be analyzed this time since the pucks stick together and move as a single object after the collision it is sufficient to use one of the post collision trajectories