AC Circuits Mock Test (Physics) MHT CET 2022

The instantaneous current in a circuit is i = sin (ωt +ø ) ampere. What is the R.M.S value of current is

A 40Ω electric heater is connected to a 200V, 50 Hz mains supply. The peak value of electric current flowing in the circuit is approximately.

E.M.F is given by e= 200sin 50t . The r.m.s value of current in a circuit of resistance 50Ω is

An alternating current of rms value 10A is passed through a 12Ω resistor. The maximum potential difference across the resistor is

A 10μF capacitor is connected across a 200 V, 50 Hz AC supply. The peak current through the circuit is:

The inductive reactance of a coil is 1000Omega. If its inductance and the frequency of A.C. supply are both doubled, then the reactance will become

An inductive coil has a resistance of 100 Ω When an AC signal of frequency 1000 Hz is applied to the coil, the voltage leads the current by 45∘ . The inductance of the coil is

When 100 V DC is applied across a solenoid, a current of 1.0 A flows in it. When 100 V AC is applied across the same coil. The current drops to 0.5A. If the frequency of the ac source is 50 Hz, the impedance and inductance of the solenoid are

220 V, 50 Hz AC source is connected to an inductance of 0.2 H and a resistance of 20 ohm in series. What is the current in the circuit:

In a series LCR circuit R=300Ω, L=0.9H, C=2μF, ω=1000rad/sω=1000rad/. The impedance of the circuit is

The inductance of a coil is 10 H. What is the ratio of its reactance when it is connected first to an A.C. source and then to a D.C. source?

In an oscillating L-C circuit the maximum charge on the capacitor is Q. The charge on the capacitor when the energy is stored equally between the electric and magnetic field is :

A resistor R, an inductor L and capacitor C are connected in series to an oscillator of frequency n. If the resonant frequency is nr, then the current lags behind voltage, when

A coil of 4mH and a capacitor of 10 muF are in series with an A.C. source along with 5Omega resistances. If inductive reactance, then the angular frequency (in rad/s) of source is

The frequency at which the inductive reactance of 2H inductance will be equal to the capacitive reactance of 2μF capacitance (nearly)

In series L-C-R circuit, the capacitance is changed from C to 2C. The inductance should be changed from L to … to obtain same resonance frequency.

If the potential difference across the inductor (3mH) is same as that across the condenser (30muF) in a series R-L-C circuit, then the frequency of the applied e.m.f. is

The rms value of current in a 50Hz AC circuit is 6A. The average value of AC current over a cycle is

A coil is self-inductance L is connected in series with a bulb B and an AC source. Brightness of the bulb decreases when :

A small signal voltage V(t)=V0sinωt is applied across an ideal capacitor C :

In a series LCR circuit, the potential drop across L,C and R respectively are 40V, 120Vand 60V. Then the source voltage is

The L-C parallel resonant circuit

A capacitor of capacitance 10μF is connected to an AC source and an AC Ammeter. If the source voltage varies as V=50√2sin100t, the reading of the ammeter is

An alternating voltage v(t)=220 sin100nt volt is applied to a purely resistance load of 50Ω. The time taken for the current to rise from half of the peak value to the peak value is

Alternating current of peak value (2π) ampere flows through the primary coil of the transformer. The coefficient of mutual inductance between primary and secondary coil is 1 henry. The peak e.m.f. induced in secondary coil is
(Frequency of AC=50Hz)

A wheel of moment of inertia 2kgm² is rotating about an axis passing through centre and perpendicular to its plane at a speed s60rad/s. Due to friction, it comes to rest in 5 minutes. The angular momentum of the wheel three minutes before it stops rotating is

When ‘W’ joule of work done on a flywheel . its frequency of rotation increases from n1 Hz to n2 Hz . The M.I of flywheel about its axis of rotation is given by

A solid cylinder of mass 2kg and radius 4cm is rotating about its axis at the rate of 3 rpm . The torque required to stop after 2π revolutions is

A particle is moving in a circular path of radius a under the action of an attractive potential  U = -k/2r² . Its total energy is

For increasing the angular velocity of a object by 10%, the kinetic energy has to be increased by