Question

A `200W` and a `100W` , both meant for operation a t `220V` are connected to a `220V` supply. The total power consumed by them will be
(i) 300W, if connected in series
(ii) 300W, if connected in parallel
(iii) `(200)/(3)W`, if connected in series
(iv) `(200)/(3)W`, if connected in parallel
A. (i) only
B. (ii), (iii)
C. (i),(iv)
D. (ii) only

Answer 1

Correct Answer - B
If rated voltage of all bulbds and applied voltage are same.
For bulbs connected in series, total power `P` consumed
`1/P = 1/(P_1) + 1/(P_2)+…`
For bulbs connected in parallel , total power `P` consumeed
`P = P_(1)+P_(2)+…`
series:
`1/P = 1/200+1/100 implies P_(1) = (200)/(3)W`
Parallel:
`P = 200+100 implies P_(2) = 300W`.