Recent content by harveysnaf

Agree, The answer (a) has all the information. Since the volume flow rate is constant, then ##\frac {dV}{dt}## is a constant. ##\frac {dr}{dt}## is variable. If you rearrange the expression to solve for ##\frac {dr}{dt}## and you get the answer to (b) and the behavior that explains (c).

It can be any surface enclosed by the wires. Your original argument is correct. For the 3 separate surfaces on the planes. Let A=(##π/4##)r2 ##\vec A## 1=A##\hat i## ##\vec A## 2=A##\hat j## ##\vec A## 3=A##\hat k## And, ##\vec B##=(5x10-3t)##\hat i## (t=time) ##\vec B## ##\cdot## ##\vec A##...