Current Electricity and Electrical InstrumentHard
Question
Two filaments of same length are connected first in series then in parallel. For the same amount of main current flowing the ratio of the heat produced is :
Options
A.1 : 2
B.4 : 1
C.1 : 4
D.2 : 1
Solution
Let main current be I & let the resistance of each wire be R.
In the first case heat produced = I2Rt + I2Rt = 2I2Rt
In the second case heat produced

Ratio =
= 4:1
In the first case heat produced = I2Rt + I2Rt = 2I2Rt
In the second case heat produced

Ratio =
= 4:1Create a free account to view solution
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