JEE & NEETJEE Physics JEE Main Physics 100+ MCQ & Answer | Page-03 | JEE & NEET MCQ February 4, 2025 DSN MARATHI 21. If a current I given by I0sin(ωt−π2) flows across an AC circuit with potential E=E0sinωt, then what is the power consumption in the circuit? A. P= E0Io/2 B. P= √2E0I0 C. P= E0I0/√2 D. P=0 Answer Option : D 22. What is the frequency of a 5μF capacitor that has a reactance of 1000 Ω? A. 200 cycle/sec B. 100/π cycle/sec C. 5000 cycles/sec D. 1000/π cycle/sec Answer Option : B 23. What is the r.m.s current value of an alternating current given by the equation of i=i1cosωt+i2sinωt? A. 1/√2(i1^2 + i2^2)^1/2 B. 1/2 ((i1^2 + i2^2)^1/2 C. 1/√ 2 (i1+i2) D. 1/√2 (i1+i2) Answer Option : A 24. What is the reciprocal of impedance? A. Admittance B. Inductance C. Reactance D. Conductance Answer Option : A 25. What is the peak value of the voltage of an electric lamp connected to a 220 V, 50 Hz supply? A. 311V B. 320 V C. 211 V D. 210 V Answer Option : A 26. Why can’t the DC ammeter measure an alternating current? A. AC cannot pass through a DC ammeter B. AC changes its direction C. AC is virtual D. The average value of a complete cycle is zero Answer Option : D 27. What is the time taken by the alternating current of 50 Hz with an r.m.s value of 10 ampere to reach from zero to a maximum value and the peak value of current? A. 2×10-2 sec and 14.24 amp B. 5×10-3 sec and 8.07 amp C. 5×10-3 sec and 14.14 amp D. 1×10-2 sec and 7.07 amp Answer Option : C 28. What is the frequency of ac mains in India? A. 120 Hz B. 60 Hz C. 50 Hz D. 30 Hz Answer Option : C 29. If the peak current is given by Ip, then how much power is dissipated by a sinusoidal ac current which flows through resistor of resistance R? A. Ip²RcosΘ B. 4/πIp²R C. 1/πIp²R D. 1/2Ip²R Answer Option : D 30. 000010 A. 111110 B. 222210 C. 333310 D. 444410 Answer Option :
21. If a current I given by I0sin(ωt−π2) flows across an AC circuit with potential E=E0sinωt, then what is the power consumption in the circuit? A. P= E0Io/2 B. P= √2E0I0 C. P= E0I0/√2 D. P=0 Answer Option : D
22. What is the frequency of a 5μF capacitor that has a reactance of 1000 Ω? A. 200 cycle/sec B. 100/π cycle/sec C. 5000 cycles/sec D. 1000/π cycle/sec Answer Option : B
23. What is the r.m.s current value of an alternating current given by the equation of i=i1cosωt+i2sinωt? A. 1/√2(i1^2 + i2^2)^1/2 B. 1/2 ((i1^2 + i2^2)^1/2 C. 1/√ 2 (i1+i2) D. 1/√2 (i1+i2) Answer Option : A
24. What is the reciprocal of impedance? A. Admittance B. Inductance C. Reactance D. Conductance Answer Option : A
25. What is the peak value of the voltage of an electric lamp connected to a 220 V, 50 Hz supply? A. 311V B. 320 V C. 211 V D. 210 V Answer Option : A
26. Why can’t the DC ammeter measure an alternating current? A. AC cannot pass through a DC ammeter B. AC changes its direction C. AC is virtual D. The average value of a complete cycle is zero Answer Option : D
27. What is the time taken by the alternating current of 50 Hz with an r.m.s value of 10 ampere to reach from zero to a maximum value and the peak value of current? A. 2×10-2 sec and 14.24 amp B. 5×10-3 sec and 8.07 amp C. 5×10-3 sec and 14.14 amp D. 1×10-2 sec and 7.07 amp Answer Option : C
28. What is the frequency of ac mains in India? A. 120 Hz B. 60 Hz C. 50 Hz D. 30 Hz Answer Option : C
29. If the peak current is given by Ip, then how much power is dissipated by a sinusoidal ac current which flows through resistor of resistance R? A. Ip²RcosΘ B. 4/πIp²R C. 1/πIp²R D. 1/2Ip²R Answer Option : D
