JEE 2020 Physics: Motional EMF and Induced Electric Field Quiz (App update required to attempt this test) for JEE & BITSAT Exams

Question 1

What is self inductance of a coil when a charge of current from 0 to 2A in 0.05 second induces an emf of 40 V in it?

Question 2

The flux linked with a circuit is given by Φ =t³ + 3t -7. The graph between time (x-axis) and induced emf (y-axis) will be

Question 3

When a battery is connected across a series combination of self-inductance L and resistance R, the variation in the current I with time t is the best represented by

Question 4

The two rails of a railway track. insulated from each other and the ground, are connected to a millivoltmeter. What is the reading of the voltmeter (in millivolts) when a train travels at a speed of 180 km/h along the track given that the vertical components of earth’s magnetic field is 0.2 ×10^—4 weber/m² and the rails are separated by 1 m ? Track is south to north.

Question 5

Direction: The question has FOUR options. ONLY ONE of these four options is the correct answer.

A conducting rod shown in fig. of mass m and length L moves on two frictionless parallel rails in the presence of uniform magnetic field directed into the page. X is load connected between parallel rails. The rod is given an initial velocity

the right and released at

. Match Col-I with Col-II

Question 6

Magnetic flux through a coil of resistance 10 Ω is changed by ∆ϕ in 0.1 s. The resulting current in the coil varies with time as shown in the figure. Then |∆ϕ| is equal to (in weber)

Question 7

Two coils, X and Y, are kept in close vicinity of each other. When a varying current, I (t), flows through coil X, the induced emf (V (t)) in coil Y, varies in the manner shown here. The variation of I(t), with time, can then be represented by the graph labelled as graph:

A.

B.

C.

D.

Question 8

An electron moves along the line AB, which lies in the same plane as a circular loop of conducting wires as shown in the diagram. What will be the direction of current induced if any, in the loop

Question 9

In a magnetic field of 0.05 T, area of a coil changes from 101 cm² to 100 cm² without changing the resistance which is 2Ω. The amount of charge that flow during this period is

Question 10

A copper rod of length l is rotated about one end perpendicular to the magnetic field B with constant angular velocity

. The induced e.m.f. between the two ends is