1. The problem statement, all variables and given/known data http://i.imgur.com/COAuag8.png 2. Relevant equations Change of momentum and Force = impulse / time. 3. The attempt at a solution I got 0.325204kg m/s for magnitude of the impulse and 8.338572195N for average force exerted by the ball on the wall. (0.00063)(26.6)(cos14)-(-0.0063)(26.6)(cos14)) = 0.325204kg m/s Force = impulse / time 0.325204/ 0.039 = 8.338572195 N Why is my answer incorrect? This is frustrating been trying to solve this for 1 hour now which is way too long for 1 question. Please check the imgur I just hate online homework especially for physics/math, because some websites are weird and gives me incorrect answers if I forget a space bar between meter and seconds (extremely dumb) while other times the question does not care or if it's not to the maximum decimal places where margin of error is 0.0000000001 or 0.1% (depends on the professors mood). Thanks in advance for your help and the removal of my headache.