Question 1 :
A coil of wire of certain radius has 100 turns and a self inductance of 15 mH. The self inductance of a second similar coil of 500 turns will be
Question 3 :
An irregular closed loop carrying a current has a shape such that the entire loop cannot lie in a single plane. If this is placed in a uniform magnetic field, the force acting on the loop
Question 4 : In an AC circuit, the current lags behind the voltage by <img style='object-fit:contain' width=27 height=20 src="https://storage.googleapis.com/teachmint/question_assets/NEET/5ea2a2a78ab67a08eba56517"> The components of the circuit are
Question 5 :
In the non-resonant circuit, what will be the nature of the circuit for frequencies higher than the resonant frequency
Question 7 :
A low-loss transformer has 230 V applied to the primary and gives 4.6 V in the secondary. Secondary is connected to a load, which draws 5 A of current. The current (in ampere) in the primary is
Question 8 : The r.m.s. value of potential difference {tex} V {/tex} shown in the figure is<br><img style='object-fit:contain' src="https://storage.googleapis.com/teachmint/question_assets/NEET/5d60f015e5db655bbf10a5bd"><br>
Question 9 :
The maximum value of AC voltage in a circuit is 707 V. Its rms value is
Question 11 : The capacity of a pure capacitor is <img style='object-fit:contain' width=52 height=20 src="https://storage.googleapis.com/teachmint/question_assets/NEET/5ea2a2304304d056cccda281"> . In dc circuits, its effective resistance will be
Question 12 :
Which of the following quantities remains constant in a step-down transformer ?
Question 13 :
The resistance of a coil for dc is in ohms. In ac, the resistance
Question 14 :
A transformer is used to light 140 W, 24 V lamp from 240 V AC mains. The current in the mains is 0.7 A. The efficiency of transformer is nearest to
Question 15 : When a sheet of metal is placed in a magnetic field, which changes from zero to a maximum value, the induced currents are set up in the direction shown in figure. What is the direction of magnetic field.<br> <img style='object-fit:contain' width='130' height='133' src="https://storage.googleapis.com/teachmint/question_assets/NEET/5ea28a218ab67a08eba54f0b">
Question 16 :
A metal disc of radius {tex} \mathrm {100 cm } {/tex} is rotated at a constant angular speed of {tex} \mathrm {60rad } / \mathrm { s } {/tex} in a plane at right angles to an external field of magnetic induction {tex}0.05 \ \mathrm { Wb } / \mathrm { m } ^ { 2 } {/tex} . The emf induced between the centre and a point on the rim will be
Question 18 :
A transformer rated at 10k W is used to connect a 5 kV transmission line to a 240 V circuit. The ratio of turns in the windings of the transformer is
Question 19 :
A 10 -meter wire is kept in east-west direction. It is falling down with a speed of 5.0 meter/second, perpendicular to the horizontal component of earth's magnetic field of {tex} 0.30 \times 10 ^ { - 4 } {/tex} weber/meter {tex} ^ { 2 } {/tex} . The momentary potential difference induced between the ends of the wire will be
Question 20 :
A coil of inductance 300{tex} \mathrm { mH } {/tex} and resistance 2{tex} \Omega {/tex} is connected to a source of voltage 2{tex} \mathrm { V } {/tex} . The current reaches half of its steady state value in
Question 21 : A conducting ring is placed around the core of an electromagnet as shown in fig. when key <img style='object-fit:contain' width='11' height='20' src="https://storage.googleapis.com/teachmint/question_assets/NEET/5ea289773c680714de9a84f8"> is pressed, the ring<br>
Question 22 :
A capacitor has capacity {tex} \mathrm { C } {/tex} and reactance {tex} \mathrm { X } {/tex} . If capacitance and frequency become double, then reactance will be
Question 23 :
The north pole of a long bar magnet was pushed slowly into a short solenoid connected to a galvanometer. The magnet was held stationary for a few seconds with the north pole in the middle of the solenoid and then withdrawn rapidly. The maximum deflection of the galvanometer was observed when the magnet was
Question 24 :
A magnet is brought towards a coil (i) speedly (ii) slowly, then the induced e.m.f /induced charge will be respectively
