Answer:
Explanation:
Resistance of motor, R = 0.05 ohm 
internal resistance of battery, r = 0.01 ohm 
Voltage of battery, V = 12 V 
(a) Total resistance, R' = R + r = 0.05 + 0.01 = 0.06 ohm 
Let the current be i. 
use Ohm's law 
i = V / R' 
i = 12 / 0.06 = 200 A 
(b) Voltage across motor, V' = i x R = 200 x 0.05 = 10 V 
(c) Power, P = i²R = 200 x 200 x 0.05 = 2000 Watt. 
(d) Total resistance, R' = 0.05 + 0.1 + 0.09 = 0.15 ohm 
i = V / R' = 12 / 0.15 = 80 A
V' = i x R = 80 x 0.05 = 4 V 
P' = i²R = 80 x 80 x 0.05 = 320 Watt