HEC USAT-CS (Computer Science) Physics: Most Repeated MCQs with Answers

HEC USAT-CS (Computer Science) Physics Most Repeated sample MCQs

1. Q1. The current in an AC circuit is given by I = 10 sin(100t). The frequency is

   • A) 50 / π Hz
   • B) 100 / (2π) Hz
   • C) 50 Hz
   • D) 100 Hz

   Answer: 50 / π Hz

2. Q2. A series LCR circuit has R = 10 ohm, L = 0.1 H, and C = 100 μF. If the frequency of the AC source is 50 Hz, what is the impedance?

   • A) 17.9 ohm
   • B) 14.1 ohm
   • C) 20 ohm
   • D) 10 ohm

   Answer: 10 ohm

3. Q3. How many significant figures in 100.0?

   • A) 1
   • B) 2
   • C) 3
   • D) 4

   Answer: 4

4. Q4. What are the dimensions of force?

   • A) MLT⁻²
   • B) ML²T⁻²
   • C) MLT⁻¹
   • D) ML²T⁻¹

   Answer: MLT⁻²

5. Q5. A series LCR circuit has R = 10 Ω, L = 0.1 H, and C = 100 μF. The resonance frequency is

   • A) 50 / π Hz
   • B) 50 Hz
   • C) 100 / π Hz
   • D) 100 Hz

   Answer: 50 / π Hz

6. Q6. The current in an AC circuit is given by I = 5 sin(100πt - π / 2). The frequency is

   • A) 50 Hz
   • B) 100 Hz
   • C) 25 Hz
   • D) 200 Hz

   Answer: 50 Hz

7. Q7. In a series LCR circuit, the voltage across the resistor is 100 V, across the inductor is 200 V, and across the capacitor is 200 V. The supply voltage is

   • A) 100 V
   • B) 200 V
   • C) 300 V
   • D) 100 √2 V

   Answer: 100 V

8. Q8. A 50 Hz AC source is connected to a capacitor of capacitance 100 μF. The reactance is

   • A) 31.83 Ω
   • B) 31.83 kΩ
   • C) 318.3 Ω
   • D) 3183 Ω

   Answer: 31.83 Ω

9. Q9. The quality factor of a series LCR circuit is given by

   • A) ωL / R
   • B) R / (ωL)
   • C) 1 / (ωCR)
   • D) ωCR

   Answer: ωL / R

10. Q10. In an AC circuit, the voltage and current are in phase. The circuit has

    • A) only resistance
    • B) only inductance
    • C) only capacitance
    • D) resistance and inductance

    Answer: only resistance

11. Q11. The rms value of an AC is 5 A. The peak value is

    • A) 5 A
    • B) 5 √2 A
    • C) 7.07 A
    • D) 3.535 A

    Answer: 7.07 A

12. Q12. A coil has an inductance of 0.1 H and resistance of 10 Ω. It is connected to an AC source of 100 V, 50 Hz. The impedance is

    • A) 10 Ω
    • B) 31.4 Ω
    • C) 33.3 Ω
    • D) 32.4 Ω

    Answer: 33.3 Ω

13. Q13. In a series LCR circuit, the voltage across the inductor is 100 V, across the capacitor is 100 V, and across the resistor is 50 V. The supply voltage is

    • A) 50 V
    • B) 50 √2 V
    • C) 100 V
    • D) 150 V

    Answer: 50 √2 V

14. Q14. In an LCR circuit, the resonance frequency is 1000 Hz. The capacitance is 100 μF. The inductance is

    • A) 0.25 mH
    • B) 0.025 H
    • C) 0.25 H
    • D) 0.025 mH

    Answer: 0.25 mH

15. Q15. The power factor of a series LCR circuit at resonance is

    • A) 0
    • B) 1
    • C) 0.5
    • D) 0.707

    Answer: 1

16. Q16. The rms voltage across a resistor is 100 V. The peak voltage is

    • A) 100 V
    • B) 141.4 V
    • C) 200 V
    • D) 70.7 V

    Answer: 141.4 V

17. Q17. In a series LCR circuit, the voltage across the resistor is 50 V and across the inductor is 100 V. The voltage across the capacitor is

    • A) 50 V
    • B) 100 V
    • C) 200 V
    • D) 100 √2 V

    Answer: 100 V

18. Q18. In an AC circuit, the current lags behind the voltage by π/3. The circuit contains

    • A) only resistance
    • B) resistance and inductance
    • C) resistance and capacitance
    • D) only capacitance

    Answer: resistance and inductance

19. Q19. The rms value of an AC is 10 A. The peak value is

    • A) 7 A
    • B) 10√2 A
    • C) 10/√2 A
    • D) 14.14 A

    Answer: 14.14 A

20. Q20. The power factor of an AC circuit is 0.5. The circuit contains

    • A) only resistance
    • B) resistance and inductance
    • C) resistance and capacitance
    • D) only inductance

    Answer: resistance and inductance

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