Two bulbs `25 W, 220 V` and `100 W, 220 V` are given . Which has higher resistance ?

Options

A. 25 w bulb
B. 100 W bulb
C. both bulbs will have equal resistance
D. resistance of bulbs cannot be compared

Answer

A

Explanation

Power of electric bulb
`P=(V^(2))/R`
So, resistance of electric bulb `R=(V^(2))/P`
Given `P_(1)=25 W , P_(2)=100 W, V_(1)=V_(2)=200V`
Therefore, for same potential difference `V, R prop 1/P`
Thus, we observe that for minimum power, resistance will be maximum and vice-versa. hence, resistance of 25W bulb is maximum and 100 W bulb is minimum.