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Question
Two resistors R and 2R are connected in series in an electric circuit. The thermal energy developed in R and 2R are in the ratio ______________ .
Options
1 : 2
2 : 1
1 : 4
4 : 1
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Solution
1 : 2
Thermal energy developed across a resistor,
U = i2Rt ,
where i is the current flowing through the resistor of resistance R for time t. Since the resistors are connected in series, the current flowing through both the resistors is same and the time for which the current flows is also same.
Thus, the ratio of the thermal energy developed in R and 2 R is 1 : 2.
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