This question seems really easy but for some reason I can't work it out. The mark scheme and examiners report are no help because it's a multiple choice question.
This question seems really easy but for some reason I can't work it out. The mark scheme and examiners report are no help because it's a multiple choice question.
First thing to always do is to check the axis and make sure the units are correct, here the time is in milliseconds so we mulitplay by x10^-3 for any calculation.
Now, Newton's second law states that Force is directly proportional to the rate of change of momentum. THe y-axis is momentum and the change is 1 (difference between 0.4 and -0.6).
We divide this by the time taken for the change in momentum to occur which is 2x10^-3 which is equal to 250N.
I think the main bit to remember here is the axis units and also that force = rate of change of momentum.