A student in the laboratory connects a 13 Ω resistor, a 24 Ω resistor, and a 41 Ω resistor in parallel and then connects the arrangement to a 43 V dc source. What is the current? What is the power? (in watts)

Answer 1

E = 43 Volts.
R1 = 13 Ohms
R2 = 24 Ohms
R3 = 41 Ohms

I = I1 + I2 + I3 =
E/R1 + E/R2 + E/R3 =
43/13 + 43/24 + 43/41 =
3.31 + 1.79 + 1.05 = 6.15 Amps. = Total
current drawn from the 43-volt source.

P = E*I = 43 * 6.15 = 264.5 Watts = Total power taken from the 43-volt source.

P1 = E^2/R1
P2 = E^2/R2
P3 = E^2/R3

P = P1 + P2 + P3.