A tennis ball of mass m=0.060kg and speed v=25m/s strikes a wall at a 45 degree angle and rebounds with the same speed at a 45 degree angle. What is the impulse (magnitude and direction)? F=deltaP=mv=deltaP/deltaT Not sure what I am doing wrong. mv=P so 0.060kg x 25m/s = 1.5Nm/s The book says the answer is 2.1kg x m/s How do I solve this. What equations am I forgetting?