JEE Physics paper for practice

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JEE Physics paper set 1
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1

A polarizer-analyzer set is adjusted such that the intensity of light coming out of the analyzer is just 10 % of
the original intensity. Assuming that the polarizer-analyzer set does not absorb any light, the angle by which the
analyser need to be rotated further to reduce the output intensity to be zero is 450


2

A 60 HP electric motor lifts an elevator with a maximum total load capacity of 2000 kg. If the frictional force on
the elevator is 4000 N, the speed of the elevator at full load is close to (Given 1 HP = 746 W, g = 10 m=s2


3

 A long solenoid of radius R carries a time (t) dependent current I(t) = I0t(1 ?? t). A ring of radius 2R is placed
coaxially near its middle. During the time instant 0  t  1, the induced current (IR) and the induced EMF (VR)


4

 Two moles of an ideal gas withCp/Cv= 5=3 are mixed with 3 moles of another ideal gas with Cp /Cv= 4=3. The value of Cp /Cvfor the mixture is


5

 The current (i1) (in A) flowing through 1 Ω
 resistor in the following circuit is


6

8. Two infinite planes each with uniform surface charge density + C=m2 are kept in such a way that the angle
between them is 30o. The electric field in the region shown between them is given by:


7

If the magnetic field in a plane electromagnetic wave is given by ~B = 310??8 sin(1:6103x + 481010t)^j T
then what will be expression for electric field?
~E
= 310??8 sin(1:6103x+481010t)^i V=m a. ~E = 310??8 sin(1:6103x+481010t)^j b. V=m
~E
= 60 sin(1:6  103x + 48  1010t)^k V=m c. ~E d. = 9 sin(1:6  103x + 48  1010t)k^ V=m


8

The time period of revolution of electron in its ground state orbit in a hydrogen atom is 1:6  10??16s: The
frequency of revolution of the electron in its first excited state (in s??1) is :


9

 A LCR circuit behaves like a damped harmonic oscillator. Comparing it with a physical spring-mass damped
oscillator having damping constant ’b’, the correct equivalence will be


10

 The radius of gyration of a uniform rod of length l about an axis passing through a point l=4 away from the center
of the rod, and perpendicular to it, is
 


11

A satellite of mass m is launched vertically upward with an initial speed u from the surface of the earth. After it
reaches height R( R = radius of earth), it ejects a rocket of mass m=10 so that subsequently the satellite moves
in a circular orbit. The kinetic energy of the rocket is (G = gravitational constant; M is the mass of earth)


12

Three point particles of mass 1 kg, 1.5 kg and 2.5 kg are placed at three corners of a right triangle of sides 4.0
cm, 3.0 cm and 5.0 cm as shown in the figure. The centre of mass of the system is at the point


13

If we need a magnification of 375 from a compound microscope of tube length 150 mm and an objective of focal
length 5 mm, the focal length of the eye-piece should be close to:


14

Speed of transverse wave on a straight wire (mass 6:0 g, length 60 cm and area of cross-section 1:0 mm2) is 90
m=s. If the Young’s modulus of wire is 16  1011Nm??2, the extension of wire over its natural length is


15

1 liter of dry air at STP expands adiabatically to a volume of 3 litres. If

γ

 = 1:4, the work done by air is
(31:4 = 4:655) (take air to be an ideal gas)