Q61.A circuit has a resistance of 12Ω and an impedance of 15Ω. The power factor of the circuit will be (1) 0.8 (2) 0.4 (3) 1.25 (4) 0.125
What This Question Tests
This question tests the direct application of the formula for power factor in an AC circuit given resistance and impedance.
Concepts Tested
Formulas Used
Power factor = R/Z
📚 NCERT Sections This Tests
3.1 — The Storage Battery Of A Car Has An Emf Of 12 V. If The Internal
Physics Class 11 · Chapter 3
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?
3.2 — A Battery Of Emf 10 V And Internal Resistance 3 Ω Is Connected To A
Physics Class 11 · Chapter 3
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?
2.5 — A Parallel Plate Capacitor With Air Between The Plates Has A
Physics Class 11 · Chapter 2
2.5 A parallel plate capacitor with air between the plates has a capacitance of 8 pF (1pF = 10–12 F). What will be the capacitance if the distance between the plates is reduced by half, and the space between them is filled with a substance of dielectric constant 6?
📋 Question Details
- Chapter
- AC Circuits
- Topic
- Power factor
- Year
- 2005
- Shift
- Unknown
- Q Number
- Q61
- Type
- MCQ
- NCERT Ref
- Class 12 Physics Ch 7: AC Circuits
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