Answer to Question #144995 in Electric Circuits for Edward Lawerence

Question

A heater with a resistance of 100  is connected to a current source with an EMF of 48 V and 

an internal resistance of 1.5 . Find the current power on the heater.

Answer 1

Current power on the heater is

$P=I^2R,$

where I - current through the heater;

R - resistance of heater.

Current through the heater is

$I=\frac{E}{R+R_{int}},$

where E - EMF of the current source;

R_int - its internal resistance.

So,

$P=\frac{E^2R}{(R+R_{int})^2}=\frac{48^2 \cdot 100}{(100+1.5)^2}=22.36 \space W$

Answer: 22.36 W