Work-Energy and Momentum

•   At this point, all the yellow boxes in the tables of the worksheet should be full.  Now is a good time to put all of the units of your data into the square brackets.
 
•    In the following, remember that to calculate a change, you subtract the initial value from the final value, e.g., ΔK = K_f - K_i. Lower-case variables refer to an individual cart and upper-case ones to both carts.
 
•   Calculate the kinetic energies of the individual carts before and after the collision and place your values into the green boxes in the second column.  At the top of the third column, calculate the change in kinetic energy of the individual carts.  Then calculate the initial and final kinetic energies of the two carts summed together, followed by the change in kinetic energy of the two carts, and finally divide the change in kinetic energy by the initial kinetic energy (the proportional change in kinetic energy).
 
•   The fourth and fifth columns for the momentum follow the same pattern as the second and third columns for kinetic energy.  The fourth column contains the x-components of the momenta for the individual carts just before and just after the collision.  The fifth column is for the values of the momentum changes for the individual carts, the total initial and final momenta, the change in total momentum, and the change divided by the initial momentum.

•   There are four fractional changes on your worksheet.  Two should be greater than 0.100, and two should be less.  Make sure you understand why before you answer the individual questions on the worksheet.