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1. A ball of mass m is projected with speed vi into a barrell of a spring gun of mass M initially at rest on a frictionless surface. The ball sticks in the barrel at the point of maximum compression of the spring. no energy is lost in friction. a) What is the speed of the spring gun after the ball comes to rest in the barrel? b) What fraction of the initial kinetic energy of the ball is lost thorough work done on the spring?
m1v1 = vf(m+M)
Vf = mvi/(M+m)
that's correct
Kfi = (1/2)mvi^2
Kf = (1/2)(m+M)[mvi/(M+m)]^2 = (1/2)m^2vi^2/(m+M)
Kf/Ki = m/(m+M)
the answer says M/(m+M)
is this a mistake, or have I missed something, I don't know how I can get M as a numerator
thanks
m1v1 = vf(m+M)
Vf = mvi/(M+m)
that's correct
Kfi = (1/2)mvi^2
Kf = (1/2)(m+M)[mvi/(M+m)]^2 = (1/2)m^2vi^2/(m+M)
Kf/Ki = m/(m+M)
the answer says M/(m+M)
is this a mistake, or have I missed something, I don't know how I can get M as a numerator
thanks