FIGURE 26-5
-In Fig. 26-5 shown below, the resistors A, B and C have resistances R, 2R, and R respectively. Which resistor dissipates the most power?
A)A
B)B
C)C
D)A & B dissipate the same amount of power.
E)All 3 resistors dissipate the same amount of power.

Question

FIGURE 26-5 
-In Fig. 26-5 shown below, the resistors A, B and C have resistances R, 2R, and R respectively. Which resistor dissipates the most power?
A)A 
B)B 
C)C 
D)A & B dissipate the same amount of power. 
E)All 3 resistors dissipate the same amount of power.

Quizplus · Accepted Answer

The power dissipated by a resistor is given by P = V^2/R. Since resistors A and C have the same resistance R, but resistor B has a resistance of 2R, resistor C will dissipate more power than resistor B. Resistor A and C have the same resistance, but the configuration of the circuit (not shown) will determine the voltage across each resistor. Assuming they are in series, the voltage across C will be the same as A, leading to the same power dissipation. However, if they are in parallel, C will dissipate more power due to its lower resistance compared to B.

FIGURE 26-5 -In Fig. 26-5 Shown Below, the Resistors A, B and A