A 45.0 kg girl is standing on a 136 kgplank. The plank, originally at rest, is free to slide on a frozenlake, which is a flat, frictionless surface. The girl begins towalk along the plank at a constant velocity of 1.43 m/s relative to the plank.
(a) What is her velocity relative to thesurface of ice?
m/s
(b) What is the velocity of the plank relative to the surface ofice?
m/s