A conducting wireframe is placed in a magnetic field that is directed into the paper. The magnetic field is increasing at a constant rate. The directions of induced current in wires \(AB\) and \(CD\) are:

            

1. \(B\) to \(A\) and \(D\) to \(C\)
2. \(A\) to \(B\) and \(C\) to \(D\)
3. \(A\) to \(B\) and \(D\) to \(C\)
4. \(B\) to \(A\) and \(C\) to \(D\)

Subtopic:  Faraday's Law & Lenz Law |
 62%
From NCERT
To view explanation, please take trial in the course.
NEET 2025 - Target Batch
Hints
Links
To view explanation, please take trial in the course.
NEET 2025 - Target Batch

A square metallic wire loop of side \(0.1\) m and resistance of \(1~\Omega\) is moved with a constant velocity in a magnetic field of \(2~\text{wb/m}^2\) as shown in the figure. The magnetic field is perpendicular to the plane of the loop and the loop is connected to a network of resistances. What should be the velocity of the loop so as to have a steady current of \(1\) mA in the loop?

          

1. \(1\) cm/sec 2. \(2\) cm/sec
3. \(3\) cm/sec 4. \(4\) cm/sec
Subtopic:  Motional emf |
 75%
From NCERT
To view explanation, please take trial in the course.
NEET 2025 - Target Batch
Hints
Links
To view explanation, please take trial in the course.
NEET 2025 - Target Batch

A conductor ABOCD moves along its bisector with a velocity of 1 m/s through a perpendicular magnetic field of 1 wb/m2, as shown in fig. If all the four sides are of 1m length each, then the induced emf between points A and D is

(1) 0

(2) 1.41 volt

(3) 0.71 volt

(4) None of the above

Subtopic:  Motional emf |
 70%
From NCERT
To view explanation, please take trial in the course.
NEET 2025 - Target Batch
Hints
To view explanation, please take trial in the course.
NEET 2025 - Target Batch

advertisementadvertisement

A conducting rod PQ of length L = 1.0 m is moving with a uniform speed v = 2 m/s in a uniform magnetic field B = 4.0 T directed into the paper. A capacitor of capacity C = 10 μF is connected as shown in figure. Then

(1) qA = + 80 μC and qB = – 80 μC

(2) qA = – 80 μC and qB = + 80 μC

(3) qA = 0 = qB

(4) Charge stored in the capacitor increases exponentially with time

Subtopic:  Motional emf |
 74%
From NCERT
To view explanation, please take trial in the course.
NEET 2025 - Target Batch
Hints
To view explanation, please take trial in the course.
NEET 2025 - Target Batch

The resistance in the following circuit is increased at a particular instant. At this instant the value of resistance is \(10~\Omega.\) The current in the circuit will be:

1. \(i = 0.5~\text{A}\) 2. \(i > 0.5~\text{A}\)
3. \(i < 0.5~\text{A}\) 4. \(i = 0\)
Subtopic:  LR circuit |
From NCERT
To view explanation, please take trial in the course.
NEET 2025 - Target Batch
Hints
Links
To view explanation, please take trial in the course.
NEET 2025 - Target Batch

Shown in the figure is a circular loop of radius r and resistance R. A variable magnetic field of induction B = B0et is established inside the coil. If the key (K) is closed, the electrical power developed right after closing the switch, at t=0, is equal to

(1) B02πr2R

(2) B010r3R

(3) B02π2r4R5

(4) B02π2r4R

Subtopic:  Faraday's Law & Lenz Law |
 61%
From NCERT
To view explanation, please take trial in the course.
NEET 2025 - Target Batch
Hints
To view explanation, please take trial in the course.
NEET 2025 - Target Batch

advertisementadvertisement

A highly conducting ring of radius R is perpendicular to and concentric with the axis of a long solenoid as shown in fig. The ring has a narrow gap of width d in its circumference. The solenoid has a cross-sectional area A and a uniform internal field of magnitude B0. Now beginning at t = 0, the solenoid current is steadily increased so that the field magnitude at any time t is given by B(t) = B0 + αt where α > 0. Assuming that no charge can flow across the gap, the end of the ring which has an excess of positive charge and the magnitude of induced e.m.f. in the ring are respectively

(1) X,

(2) X πR2α

(3) Y, πA2α

(4) Y, πR2α

Subtopic:  Faraday's Law & Lenz Law |
From NCERT
To view explanation, please take trial in the course.
NEET 2025 - Target Batch
Hints
To view explanation, please take trial in the course.
NEET 2025 - Target Batch

A rectangular loop with a sliding connector of length \(l= 1.0\) m is situated in a uniform magnetic field \(B = 2T\) perpendicular to the plane of the loop. Resistance of connector is \(r=2~\Omega\). Two resistances of \(6~\Omega\) and \(3~\Omega\) are connected as shown in the figure. The external force required to keep the connector moving with a constant velocity \(v = 2\) m/s is:

          
1. \(6~\text{N}\)
2. \(4~\text{N}\)
3. \(2~\text{N}\)
4. \(1~\text{N}\)

Subtopic:  Motional emf |
 59%
From NCERT
To view explanation, please take trial in the course.
NEET 2025 - Target Batch
Hints
Links
To view explanation, please take trial in the course.
NEET 2025 - Target Batch

A wire cd of length l and mass m is sliding without friction on conducting rails ax and by as shown. The vertical rails are connected to each other with a resistance R between a and b. A uniform magnetic field B is applied perpendicular to the plane abcd such that cd moves with a constant velocity of

(1) mgRBl

(2) mgRB2l2

(3) mgRB3l3

(4) mgRB2l

Subtopic:  Motional emf |
 79%
From NCERT
To view explanation, please take trial in the course.
NEET 2025 - Target Batch
Hints
To view explanation, please take trial in the course.
NEET 2025 - Target Batch

advertisementadvertisement

A conducting rod AC of length 4l is rotated about a point O in a uniform magnetic field B directed into the paper. AO = l and OC = 3l. Then

(1) VAVO=Bωl22

(2) VOVC=72Bωl2

(3) VAVC=4Bωl2

(4) VCVO=92Bωl2

Subtopic:  Motional emf |
 60%
From NCERT
To view explanation, please take trial in the course.
NEET 2025 - Target Batch
Hints
To view explanation, please take trial in the course.
NEET 2025 - Target Batch