This is a simple problem, but for some reason i can't come up wit the answer. Im i using the wrong formula? A base ball is traveling and strikes a catchers mitt, bringing it to rest. the mitt recoils 11 cm. m=.14 kg vi=45 m/s vf=0 m/s d=11cm (.11 m) i used the formula vf^2=vi^2+2ad to get the accelearation the used F=ma for force, but i got 1289N. It seems a little much for a ball, is it right or did i use the wrong formula? please help!