1
JEE Main 2016 (Online) 10th April Morning Slot
+4
-1
Out of Syllabus
A fighter plane of length 20 m, wing span (distance from tip of one wing to the tip of the other wing) of 15 m and height 5 m is flying towards east over Delhi. Its speed is 240 ms−1. The earth’s magnetic field over Delhi is 5 $$\times$$10−5 T with the declination angle ~ 0o and dip of $$\theta$$ such that sin $$\theta$$ = 2/3 . If the voltage developed is VB between the lower and upper side of the plane and VW between the tips of the wings then VB and VW are close to :
A
VB = 45 mV; VW = 120 mV with right side of pilot at higher voltage
B
VB = 45 mV; VW = 120 mV with left side of pilot at higher voltage
C
VB = 40 mV; VW = 135 mV with right side of pilot at high voltage
D
VB = 40 mV; VW = 135 mV with left side of pilot at higher voltage
2
JEE Main 2016 (Offline)
+4
-1
Out of Syllabus
Hysteresis loops for two magnetic materials $$A$$ and $$B$$ are given below :

These materials are used to make magnets for electric generators, transformer core and electromagnet core. Then it is proper to use :

A
$$A$$ for transformers and $$B$$ for electric generators.
B
$$B$$ for electromagnets and transformers.
C
$$A$$ for electric generators and transformers.
D
$$A$$ for electromagnets and $$B$$ for electric generators.
3
JEE Main 2014 (Offline)
+4
-1
The coercivity of a small magnet where the ferromagnet gets demagnetized is $$3 \times {10^3}\,A{m^{ - 1}}.$$ The current required to be passed in a solenoid of length $$10$$ $$cm$$ and number of turns $$100,$$ so that the magnet gets demagnetized when inside the solenoid, is :
A
$$30$$ $$mA$$
B
$$60$$ $$mA$$
C
$$3$$ $$A$$
D
$$6A$$
4
JEE Main 2013 (Offline)
+4
-1
Two short bar magnets of length $$1$$ $$cm$$ each have magnetic moments $$1.20$$ $$A{m^2}$$ and $$1.00$$ $$A{m^2}$$ respectively. They are placed on a horizontal table parallel to each other with their $$N$$ poles pointing towards the South. They have a common magnetic equator and are separated by a distance of $$20.0$$ $$cm.$$ The value of the resultant horizontal magnetic induction at the mid-point $$O$$ of the line joining their centres is close to $$\left( \, \right.$$ Horizontal component of earth's magnetic induction is $$3.6 \times 10.5Wb/{m^2})$$
A
$$3.6 \times 10.5\,\,Wb/{m^2}$$
B
$$2.56 \times 10.4\,\,Wb/{m^2}$$
C
$$3.50 \times 10.4\,\,Wb/{m^2}$$
D
$$5.80 \times 10.4\,Wb/{m^2}$$
EXAM MAP
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