Q1: When parallel resistors are of three different values, which has the greatest power loss?

ANS:A - The smallest resistance

The right answer should be the smallest resistance since from the formula P = V^2/R if R is small Power is greater.

In formula P = I^2 *R if R is small I would be large and P would also be the largest. In the formula P= I*V since R is small then I is large and since it is parallel so V is constant therefore P would still be the largest.

Ex. Given 3 components in parallel with 60 V source.

R1 = 20 ohms, V1 = 60V, I = 3A, P=IV = 180 W, P=V^2/R = 180W, P=I^2 * R= 180W.
R2 = 40 ohms, V2 = 60V, I = 1.5A, P=IV = 90W, P=V^2/R = 90W, P=I^2 * R= 180W.
R3 = 60 ohms, V3 = 60V, I = 1 A, P=IV = 60W, P=V^2/R = 60W, P=I^2 * R= 180W.

In conclusion, the one with the smallest resistance will always has the largest power.