162k views
2 votes
Two light bulbs, one rated 50 W and a second rated 100 W are both supposed to be connected to a 110 V source of emf. Which of the following is true?

a. The 50W bulb has twice the resistance as the 100W bulb
b. The 50W bulb has four times the resistance of the 100W bulb
c. The 50W bulb has Half the resistance of the 100W bulb
d. The 50W bulb has one quarter the resistance of the 100W bulb

User Pesche
by
8.4k points

1 Answer

6 votes

The correct answer is c. The 50W bulb has half the resistance of the 100W bulb. This is because the power consumed by a light bulb is given by P = V^2/R, where P is power, V is voltage, and R is resistance. Since both bulbs are connected to the same 110 V source, the power consumed by the 50W bulb must be half of the power consumed by the 100W bulb. Solving for R, we get R = V^2/P. Since V and P are constant for both bulbs, the resistance of the 50W bulb must be half of the resistance of the 100W bulb.

User Mirmdasif
by
8.6k points