Answer:
Explanation:
Ohm's law is define by the formula
V = IR where I is current in A, R is resistance in ohms
to calculate the resistance we use the formula above
I = 185 mA / 1000 = 0.185 A
case 1, R = V / I = 12 V / 0.185 A = 64.86 ohms
case 2, R = V / I = 90 / 1.25 A = 72 ohms
a) the resistor is not ohmic since there is no linear relationship between R and V ( as voltage increases, resistance ought to also increase)
b) rate of Joule heating in the case 1, P, power = IV = 0.185 A × 12 = 2.22 W
case 2, P = IV = 1.25 A × 90 V = 112.5 W