A child of mass mc is riding a sled of mass ms moving freely along an icy

Question:

A child of mass mc is riding a sled of mass ms moving freely along an icy frictionless surface at speed v0. If the child falls o® the sled, derive a formula for the change in speed of the sled. (Note: energy is not conserved!) WRONG WRONG WRONG ?????????????? Speed of sled remains same - person keeps moving when fall o® ???????