Question

3 bulbs of 60w are connected in parallel .What is the resultant power

Answer 1

Answer:

100W.

Explanation:

The equivalent power will be 100W.

explanation : when two bulbs of power 60w and 40w are connected in series , then we have to find power of their combination.

we know, power,P=I^2*R

where I denotes current passing through the circuit and R denotes resistance of bulb.

so, resistance of first bulb , R1 = P1/I^2

= 60/I^2 .....(1)

Similarly, resistance of 2nd bulb, R2 = P2/I^2

= 40/I^2 ........(2)

now , if R1and R2 are joined in series then,

equivalent resistance, Req = R1 + R

or P/I^2 = 60/I^2 + 40/I^2

or, P = 60 + 40

hence, Peq = 60+40=100W

hence, power of their combination is 100W.