An average net force of 25.0 N acts right on an object for 7.20 x 10^-1s. What is the change in momentum of the object?

I know how to do this question but just I cannot understand about the question asking 4kg ball. The question is " A 2 kg ball moving at 7m/s strikes a 1 kg ball at rest.The 2kg ball continues to move in the same direction at 3m/s. a) Find the velocity of the 4kg ball. b) How much the kinetic...

I know how to do this question but just I cannot understand about the question asking 4kg ball. The question is " A 2 kg ball moving at 7m/s strikes a 1 kg ball at rest.The 2kg ball continues to move in the same direction at 3m/s. a) Find the velocity of the 4kg ball. b) How much the kinetic...

http://www.smartphysics.com/images/content/mechanics/ch11/cartruckcollisionnew.png A blue car with mass m@car = 444 kg is moving east with a speed of vc = 23 m/s and collides with a purple truck with mass m@truck = 1273 kg that is moving south with a speed of vt = 12 m/s . The two collide and...

;D Sorry if I sound very stupid... A golfer hits a golf ball of mass 51g and the ball leaves the club with a velocity of 80m/s. Assuming that the ball and club are in contact for 0.0006s, find the ball's final momentum and the average force exerted by the club on the ball Next : diver dive...