Question #8dc0a Physics Work and Energy Conservation of Energy 1 Answer P dilip_k Feb 12, 2017 Given #"Mass of the ball "m=300g=0.3kg# #"Initial velocity of the ball "u=-8m"/"s# #"Final velocity of the ball "v=+6m"/"s# #"Force applied on the ball by the wall "F=2000N# #"Let the time of ball-wall contact be "=t s# So by Newton's law we have #F=(m(v-u))/t# #=>2000=(0.3xx(6-(-8)))/t# #=>t=4.2/2000=2.1xx10^(-3)s=2.1ms# Answer link Related questions Can energy be absorbed when matter changes? What is kinetic energy? Can energy be changed from one form to another? What is an example of electrical energy transforming into light energy? How does the law of conservation of energy apply to chemical changes? What is the conservation of energy? What is conservation of energy? What are some examples of the principle of conservation of energy? What is the joule apparatus? Why does a perpetual motion machine of the first kind violate the law of conservation of energy? See all questions in Conservation of Energy Impact of this question 1461 views around the world You can reuse this answer Creative Commons License