Physics-
General
Easy
Question
Two identical square rods of metal are welded end to end as shown in figure (i), 20 calories of heat flows through it in 4 minutes. If the rods are welded as shown in figure (ii), the same amount of heat will flow through the rods in
- 1 minute
- 2 minutes
- 4 minutes
- 16 minutes
The correct answer is: 1 minute
(R = Thermal resistance)
Þ 
(
Q and 
are same)
Þ 
Þ
(Series resistance 
and parallel resistance 
)
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