301 An inductive coil has a resistance of 100Ω. When an AC signal of frequency 1000Hz is fed to the coil the applied voltage leads the current by 45Ω. What is the inductance of the coil ? Physics Medium Full question → A 10mH B 12mH C 16mH D 20mH
302 An A.C series circuit containing 4Ω resistance and 3Ω inductive reactance. The impedance of the circuit is______________? Physics Medium Full question → A 1Ω B 5Ω C 7Ω D 7Ω
303 At resonance the value of the power factor in an L-C-R series circuit is_______________? Physics Medium Full question → A Zero B 2 C 1 D Not definite
304 A choke is used as a resistance in_________________? Physics Medium Full question → A DC circuit B AC circuits C Both AC and DC circuit D Full wave rectifier circuit
305 A 10Ω electric heater is connected to a 220V 50Hz mains supply. What is the peak value of the potential difference across the heater element ? Physics Medium Full question → A 220V B 220/ 2V C 110V D 220 √2V
306 The frequency of a circuit consisting of a capacitance C and a resistor R is________________? Physics Medium Full question → A C/R B R/C C 1/RC D 1/ 2RC
307 What is the self-inductance of a coil in which an induced emf of 2V is set up when the current changes at the rate of 4 As-1 ? Physics Medium Full question → A 0.5 mH B 0.5H C 2.0H D 8.0H
308 When a pure inductor of inductance L and a pure capacitor of capacitance C are connected in parallel to a sinusoidal potential difference V the potential difference across both L & C will be_______________? Physics Medium Full question → A Same B Different C At L will be more than at C D At L will be less than at C
309 Ammeter connected in an AC circuit measures______________? Physics Medium Full question → A The exact value of the current B RMS value of the current C The net value of the current D The peak value of the current
310 A wire of resistance R is coiled inductively so that its inductance is L. The impedance of the coil at a frequency of f is_______________? Physics Medium Full question → A (R+2πfL) B R+1/2πfL C (R2+f2L2) D (R2+4π2f2L2)
311 If a glass plate is inserted in between the plate of a capacitor in series with a lighted bulb the brightness of the bulb________________? Physics Medium Full question → A Remains same B Brightness increases C Brightness decreases D No light
312 A 100µF capacitor with a 12V source in series having frequency 50Hz will offer a capacitive reactance of about______________? Physics Medium Full question → A 32Ω B 62Ω C 50Ω D 100Ω
313 In the capacitive circuit the current___________________? Physics Medium Full question → A Lags behind voltage by π/2 B Is in phase with voltage C Opposite in phase of voltage by π D Leads forward the voltage by π/2
314 When A.C current passes through a capacitor then the current relationship will be_______________? Physics Medium Full question → A The current lead voltage by phase angle is 90 degrees B The voltage leads current by phase angle is 90 degrees C The current lead voltage by phase angle is 45 degrees D The voltage leads current by phase angle is 45 degrees
315 pure resistor circuit the voltage and current are_______________? Physics Medium Full question → A Lagging each other B They are at 90? phase difference C They have zero phase difference D No phase difference
316 An alternating current is represented by the equation I = I∫sinπt which of the following equation represents an alternating current of frequency and amplitude twice that of the above current ? Physics Medium Full question → A I = 2I∫Sin(πt/2) B I = 2I∫Sin(2πt) C I = 2ISinπt D I = I∫sin(2πt)
317 To find the r.m.s value of an alternating current mathematically we need to have ________________? Physics Medium Full question → A Mean value of I2 B Square root of mean value of I2 C Square root of I2 D Square of 1/2
318 A capacitor of capacitance 30µF is charged by a constant current of 10mA. If initially, the capacitor was uncharged what is the time taken for the potential difference across the capacitor to reach 300V ? Physics Medium Full question → A 0.9sec B 15 sec C 1.5x105sec D 0.9x102sec
319 Electromagnetic waves emitted from antenna are________________? Physics Medium Full question → A Stationary B Longitudinal C Transverse D All the above
320 Electromagnetic waves transport___________________? Physics Medium Full question → A Energy B Momentum C Mass D Heat