Being Impulsive About Momentum Change - Questions 15 Help

During a collision, an object experiences an impulse that changes its momentum. The impulse is equal to the momentum change. The impulse is the product of Force•∆Time. The momentum change is the product of Mass•∆Velocity. One can use the Force•∆Time = Mass•∆Velocity relationship to determine the set of collision parameters required to change the object's momentum from the initial state value to the final state value.

The diagram in this question shows an object mass (in kg) and a pre-collision and a post-collision velocity value. Also notice that there is a change in direction of the object. It changes from moving in the + direction (right) to moving in the negative direction. So the final velocity is a negative velocity. The velocity values can be used to calculate a velocity change (∆v). You can calculate velocity change by subtracting the initial value from the final value (which is negative). The result will be a negative velocity change. The momentum change can be calculated by multiplying mass by ∆velocity. You will need to calculate this momentum change (∆p) before you can answer the question. It would be wise to write down the result because you will be using it again.
 
This question includes two different "impulses" or collisions. So you will need to pick two answers that when combined (added together) provide the momentum change you just calculated. The principle that should guide your answer selection is that the momentum change is equal to the total or combined impulse.
 
Of the five answer options, two include impulse values, one is a momentum change value, and the final two are both combinations of force-∆time values. We recommend that you first calculate the impulse values from the provided force-∆time values. You would be wise to write down the values you calcuate. Once done, inspect the five answer options and use a trial and error method to find two options which add together to give the momentum change that you have calculated.