A 70.0 kg archer standing on frictionless ice shoots a 200g arrow at a speed of 100m/s. What is the recoil speed of the archer?
200g is 0.2kg.
(0.2 x 100)/70 = 0.2857m/sec.
by law of conservation of momentum
70*v+0.2*100=0 as archer & arrow are at rest in the beginning
=>recoil speed of the archer =20/70=0.285m/s