City College Of Education

A boy wishes to make a catapult out of a rubber band of width 9mm…

A boy wishes to make a catapult out of a rubber band of width 9mm and thickness 1.55mm.Determine the length of the band that he must use so that when he stretches it by 0.25 of its natural length and releases it, the velocity of a pebble of mass 0.006kg will be 30m/s.Take the Young modulus of the rubber to be 4*10^2N/m^2.?