In the event of an emergency, a nuclear reactor is shut down by dropping the control rod R, having a weight of 20 lb, into the reactor core C. If the rod is immersed in “heavy” water, which offers a drag resistance to downward motion of F_D = (0.25v) lb, where v is the velocity of the rod in ft/s, determine the distance s it must descend into the reactor core when it attains a speed of 15 ft/s. The rod is released from rest when s = 0. Neglect the effects of buoyancy.

Transcribed Image Text:

S R FD