Five resistors are connected as shown in the diagram. The potential difference between points A and B is 25 V.
-How much energy is dissipated in the 1.8-$\varOmega$ resistor in 4.0 seconds?
A)18 J
B)28 J
C)55 J
D)64 J
E)93 J

Question

Five resistors are connected as shown in the diagram. The potential difference between points A and B is 25 V. 
-How much energy is dissipated in the 1.8-$\varOmega$ resistor in 4.0 seconds?
A)18 J 
B)28 J 
C)55 J 
D)64 J 
E)93 J

Quizplus · Accepted Answer

To find the energy dissipated in the 1.8 Ω resistor, we need to first find the current passing through it using Ohm's Law:
V = IR
25 V = I * (1.8 Ω + 0.6 Ω + 1 Ω)
I = 8.33 A

Now, we can use the formula for the energy dissipated in a resistor:
E = I^2Rt
E = (8.33 A)^2 * 1.8 Ω * 4.0 s
E = 55.3 J
Rounding off to two significant figures, the answer is 55 J. Therefore, the best choice is C.

Five Resistors Are Connected as Shown in the Diagram Ω\varOmegaΩ Resistor in 4

Five Resistors Are Connected as Shown in the Diagram $\varOmega$ Resistor in 4