If H is the heat required to heat the water, then
P1×60=H⇒P1=60H and P2×20=H⇒P2=20H
When the coils are connected in parallel their powers will get added. If the required time now is t, then
(P1+P2)t=H⇒t=60H+20HH=15min
JEE Main 2022 — Physics Electromagnetism
Two coils require 20 minutes and 60 minutes respectively to produce same amount of heat energy when connected separately to the same source. If they are connected in parallel arrangement to the same source; the time required to produce same amount of heat by the combination of coils, will be _____ min.
Held on 29 Jun 2022 · Verified 6 Jul 2026.
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