A voltage V across a resistance R generates a current I=V/R. If a constant voltage of 17 volts is put across a resistance that is increasing at a rate of 0.3 ohms per second when the resistance is 7 ohms, at what rate is the current changing? (Give units.)

Answer 1

I = 17/R
dI/dt = -17/R^2 dR/dt
now plug in your numbers.
dI/dt = -17/7^2 * 0.3 = -0.104 amps/sec