Q15.An electrical power line, having a total resistance of 2Ω, delivers 1 kW at 220 V. The efficiency of the transmission line is approximately : (1) 72% (2) 91% (3) 85% (4) 96%
What This Question Tests
This problem involves calculating the current in a power line, determining power loss due to line resistance, and then finding the transmission efficiency.
Concepts Tested
Formulas Used
P = VI
P_loss = I²R_line
Efficiency = (P_output / P_input) * 100%
📚 NCERT Sections This Tests
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3.2 A battery of emf 10 V and internal resistance 3 Ω is connected to a resistor. If the current in the circuit is 0.5 A, what is the resistance of the resistor? What is the terminal voltage of the battery when the circuit is closed?
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3.1 The storage battery of a car has an emf of 12 V. If the internal resistance of the battery is 0.4 Ω, what is the maximum current that can be drawn from the battery?
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📋 Question Details
- Chapter
- Current Electricity
- Topic
- Electrical Power and Efficiency
- Year
- 2020
- Shift
- 05 Sep Shift 1
- Q Number
- Q15
- Type
- MCQ
- NCERT Ref
- Class 12 Physics Ch 3: Current Electricity
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