Electromagnetic Induction Test

Question 1
1 / -0

A conducting square loop of side $$l$$ and resistance R moves in its plane with a uniform velocity $$v$$ perpendicular to one of its sides. A uniform and constant magnitude field B exists along the perpendicular to the plane of the loop as shown in figure. The current induced in the loop is

A
$$\displaystyle \frac{Blv}{R}$$ clockwise

B
$$\displaystyle \frac{Blv}{R}$$ anti-clockwise

C
$$\displaystyle \frac{2 Blv}{R}$$ anti-clockwise

D
zero

Question 2
1 / -0

A tank containing a liquid has turns of wire wrapped around it, causing it to act as an inductor. The liquid content of the tank can be measured by using its inductance to determine the height of the liquid level in the tank. The inductance of the tank changes from a value of $$L_0$$ corresponding to a relative permeability of $$1$$ when the tank is empty to value $$L_f$$ corresponding to a relative permeability $$X_m$$ (relative permeability of liquid) when the tank is full. The appropriate electronic circuit can determine the inductance correct upto $$5$$ significant figures and thus the effective relative permeability of the combined air and liquid within the rectangular has height $$D$$. The height of the liquid level in the tank is $$d$$. Ignore the fringing effects. Assume tank is fitted with $$Hg X _{Hg} = 2.9 \times 10^5$$.
Express $$d$$ as a function of $$L$$, inductance corresponding to a certain liquid height $$L_0, L_f$$ and $$D$$.

A
$$\displaystyle d =\frac{(L - L_0)D}{L_f - L_0}$$

B
$$\displaystyle d =\frac{LD}{L_f - L_0}$$

C
$$\displaystyle d =\frac{(L - L_0)D}{L_f }$$

D
None of these

Question 3
1 / -0

Two conducting rings of radii r and 2r move in opposite directions with velocities 2$$v$$ and $$v$$ respectively on a conducting surface $$S$$. There is a uniform magnetic field of magnitude $$B$$ perpendicular to the plane of the rings. The potential difference between the highest points of the two rings is

A
$$zero$$

B
$$2rvB$$

C
$$4 rvB$$

D
$$8 rvB$$

Question 4
1 / -0

A coil of insulating wire is connected to battery. If it is moved towards a galvanometer then its point gets deflected because

A
the coil behaves like a magnet

B
induced current is produced in the coil

C
the number of turns in the galvanometer coil remains constant

D
none of the above

Question 5
1 / -0

A 1.2 m wide railway track is parallel to magnetic meridian. The vertical component of earth's magnetic field is 0.5 Gauss. When a train runs on the rails at a speed of 60 Km/hr, then the induced potential difference the ends of its axle will be

A
$$10^{-4}$$ V

B
$$2 \times 10^{-4}$$ V

C
$$10^{-3}$$ V

D
zero

Question 6
1 / -0

Two coils P and Q are lying parallels and very close to each other. Coil P is connected to an AC source whereas Q is connected to a sensitive galvanometer. On pressing key K

A
small variations are observed in the galvanometer for applied 50 Hz voltage

B
deflections in the galvanometer can be observed for applied voltage of 1 Hz to 2 Hz.

C
no deflection in the galvanometer will be observed

D
constant deflection will be observed in the galvanometer for 50 Hz supply voltage

Question 7
1 / -0

When the number of turns per unit length in a solenoid is doubled then its coefficient of self induction will become

A
half

B
double

C
four times

D
unchanged

Question 8
1 / -0

The number of turns in an air core solenoid of length 25 cm and radius 4 cm is 100. Its self inductance will be

A
$$5 \times 10^{-4} H$$

B
$$2.5 \times 10^{-4} H$$

C
$$5.4 \times 10^{-3} H$$

D
$$2.5 \times 10^{-3} H$$

Question 9
1 / -0

A cycle wheel with 64 spokes is rotating with N rotations per second at right angles to horizontal component of magnetic field. The induced emf generated between its axle and rim is E. If the number of spokes is reduced to 32 then the value of induced emf will be :

A
E

B
2E

C
$$\displaystyle \frac{E}{2}$$

D
$$\displaystyle \frac{E}{4}$$

Question 10
1 / -0

The coefficient of mutual induction between two coils is 4 H. If the current in the primary reduces from 5A to zero in 10$$^{-3}$$ second then the induced emf in the secondary coil will be

A
$$10^4$$ V

B
$$25 \times 10^3$$ V

C
$$2 \times 10^4 $$ V

D
$$15 \times 10^3$$ V

Submit Test

Electromagnetic...

Question 1

$$\displaystyle \frac{Blv}{R}$$ clockwise

$$\displaystyle \frac{Blv}{R}$$ anti-clockwise

$$\displaystyle \frac{2 Blv}{R}$$ anti-clockwise

zero

Question 2

$$\displaystyle d =\frac{(L - L_0)D}{L_f - L_0}$$

$$\displaystyle d =\frac{LD}{L_f - L_0}$$

$$\displaystyle d =\frac{(L - L_0)D}{L_f }$$

None of these

Question 3

$$zero$$

$$2rvB$$

$$4 rvB$$

$$8 rvB$$

Question 4

the coil behaves like a magnet

induced current is produced in the coil

the number of turns in the galvanometer coil remains constant

none of the above

Question 5

$$10^{-4}$$ V

$$2 \times 10^{-4}$$ V

$$10^{-3}$$ V

zero

Question 6

small variations are observed in the galvanometer for applied 50 Hz voltage

deflections in the galvanometer can be observed for applied voltage of 1 Hz to 2 Hz.

no deflection in the galvanometer will be observed

constant deflection will be observed in the galvanometer for 50 Hz supply voltage

Question 7

half

double

four times

unchanged

Question 8

$$5 \times 10^{-4} H$$

$$2.5 \times 10^{-4} H$$

$$5.4 \times 10^{-3} H$$

$$2.5 \times 10^{-3} H$$

Question 9

E

2E

$$\displaystyle \frac{E}{2}$$

$$\displaystyle \frac{E}{4}$$

Question 10

$$10^4$$ V

$$25 \times 10^3$$ V

$$2 \times 10^4 $$ V

$$15 \times 10^3$$ V

User

Question Analysis

Results Announcement on: coming Monday

Stay Tuned: We’ll update you on your result via email or SMS.