1
JEE Main 2022 (Online) 28th June Evening Shift
+4
-1

A coil is placed in a time varying magnetic field. If the number of turns in the coil were to be halved and the radius of wire doubled, the electrical power dissipated due to the current induced in the coil would be :

(Assume the coil to be short circuited.)

A
Halved
B
C
The same
D
Doubled
2
JEE Main 2022 (Online) 28th June Morning Shift
+4
-1

An infinitely long hollow conducting cylinder with radius R carries a uniform current along its surface.

Choose the correct representation of magnetic field (B) as a function of radial distance (r) from the axis of cylinder.

A
B
C
D
3
JEE Main 2022 (Online) 28th June Morning Shift
+4
-1

A radar sends an electromagnetic signal of electric field (E0) = 2.25 V/m and magnetic field (B0) = 1.5 $$\times$$ 10$$-$$8 T which strikes a target on line of sight at a distance of 3 km in a medium. After that, a part of signal (echo) reflects back towards the radar with same velocity and by same path. If the signal was transmitted at time t = 0 from radar, then after how much time echo will reach to the radar?

A
2.0 $$\times$$ 10$$-$$5 s
B
4.0 $$\times$$ 10$$-$$5 s
C
1.0 $$\times$$ 10$$-$$5 s
D
8.0 $$\times$$ 10$$-$$5 s
4
JEE Main 2022 (Online) 27th June Morning Shift
+4
-1

The susceptibility of a paramagnetic material is 99. The permeability of the material in Wb/A-m, is :

[Permeability of free space $$\mu$$0 = 4$$\pi$$ $$\times$$ 10$$-$$7 Wb/A-m]

A
4$$\pi$$ $$\times$$ 10$$-$$7
B
4$$\pi$$ $$\times$$ 10$$-$$4
C
4$$\pi$$ $$\times$$ 10$$-$$5
D
4$$\pi$$ $$\times$$ 10$$-$$6
JEE Main Subjects
Physics
Mechanics
Electricity
Optics
Modern Physics
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