A mass is moving at 10 m/s in the +x direction and it collidesin a perfectly elastic collision with a mass of 2 kg moving in the-x direction. The collision takes places in 0.21 seconds and afterthe collision the mass that was moving in the +x direction ismoving in the -x direction at 9 m/s and the mass that was moving inthe -x direction is moving in the +x direction at 13 m/s. What isthe magnitude of the average force, in Newtons, on the first masswhich was originally moving in the +x direction before thecollision?
