Class 12th Physics 2018 Set3 Delhi Board Paper Solution
Two Electric bulbs P and Q have their resistances in the ratio of 1:2. They are connected in series across a battery. Find the ratio of the power dissipation in these bulbs.
Let ratio be x
Rp = x (Resistance of bulb P)
Rq = 2x (Resistance of bulb Q)
as, P = VI = V. V / R
Pp / Pq = V2 / Rp x Rq / V2 [In series potential will be same]
Pp / Pq = 2x / x = 2 : 1
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