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SOLUTION & ANSWER FOR
VITEEE-2008 VERSION - P PART
1 [PHYSICS] 1. In nature,
the electric charge of any system is always Ans: Quantisation
of charge Choice
(D) 2. The energy stored in the capacitor as shown
in
Fig.
(a) is 4.5 ΄
10-
6 J. If the battery is replaced by
Ans:
=
4.5 ΄
10-
6 J
Choice (B) 3. Equal amounts of a metal are converted into
cylindrical
wires of different lengths (L) and cross-sectional
Ans: R
=
Choice (C) 4. If the force exerted by an electric dipole
on a
charge
q at a distance of 1 m is F, the force
Ans:
Choice (D) 5. A solid sphere of radius R
1 and
volume charge density r
=
Ans: Q
in
=
=
=
4p
R22s
Choice (C) 6. A solid spherical conductor of radius R has
a
spherical
cavity of radius a9a < R) at its centre. A charge +Q is kept at
the center.
Choice (B) 7. A
cylindrical capacitor has charge Q and length L. If both
Ans: U
1
=
U
2
=
Choice (B) 8. Three
resistances of 4 W
each are connected as shown in
figure. If the point D divides the resistance
Choice (C) 9. The
resistance of a metal increases with increasing
Ans: Vibration
of lattice ions increases with
temperature Choice (B) 10. In the absence
of applied potential, the electric current flowing through-
Ans: Thermal
velocity of electrons is in random
directions Choice (C) 11. A meter bridge
is used to determine the resistance of an unknown wire by measuring the balance
point length l. If the wire is
replaced by
Ans: 12. Identify the
INCORRECT statement regarding
Ans: Supercurrent
always flows on the surface
of
the superconductor Choice (B) 13. A sample of
HCl gas is placed in an electric field of 3 ΄
104 NC-
1. The
dipole moment of each HCl molecule is
Ans: t
= pE Choice (C) 14. When a
metallic plate swings between the
Ans: Lenzs
law Choice (C) 15. When an
electrical appliance is switched on, it responds almost-
Ans: Electromagnetic
waves travel with the
speed
of light Choice (B) 16. Two identical
incandescent light bulbs are connected as shown in the figure. When the circuit
is an AC voltage source
Ans: At
resonance XL = XC Choice (B) 17. A transformer
rated at 10 kW is used to connect a 5 kV transmission line to a 240 V circuit.
The ratio
Ans: n
=
Choice (B) 18. Three solenoid
coils of same dimension, same number of turns and same number of layers of
winding are taken. Coil 1 with inductance L1 was wound using a Mn
wire of resistance 11 W
/ m;
Ans: Alternate
winding in opposite direction
total
flux = 0 Choice (C) 19. Light travels
with a speed of 2 ΄
108 m/s in crown glass of
refractive index 1.5. What is the speed of light
Ans: n
1v1
= n2v2 Choice (B) 20. A parallel
beam of fast moving electrons is incident normally on a narrow slit. A screen is
placed at a large distance from the slit.
Ans: sinq
=
Choice (C) 21. Two beams of
light will not give rise to an
Ans: Since
the polarization vectors are
perpendicular
their vector sum Ή
0 Choice (C) 22. A slit of
width `a is illuminated with a monochromatic light of wavelength l
from a
distant source and the diffraction pattern
Ans: sinq
=
Choice (B) 23. A thin film of
soap solution (n = 1.4) lies on the top of a glass plate (n = 1.5). When
visible light is incident almost normal to the plate, two adjacent reflection
Ans: n
1l
1 = n2l
2
2n
1
= 3n2
ή
n1
= 3
d
=
Choice (B) 24. If the speed
of a wave doubles as it passes from shallow water into deeper water,
Ans: c
= fl
Choice (C) 25. A light whose
frequency is equal to 6 ΄
1014 Hz is incident on a
metal whose work function is
Ans: hu
= f
+ K.E Choice (C) 26. An electron
microscope is used to probe the atomic arrangements to a resolution of
Ans:
Choice (D) 27. Which phenomenon
best supports the theory that matter
Ans: Electrons
behave also as waves of l
=
Choice (B) 28. The
radioactivity of a certain material drops to
Ans: Activity
changes from A0 to A0/16 implies 4 half-lives. Choice (C) 29. An observer
`A sees an asteroid with a radioactive element moving by at a speed = 0.3 c
and measures the radioactivity decay time to be TA. Another observer
`B
Ans: Moving
clocks are slower TB < TA Choice (A) 30. 234U
has 92 protons and 234 nucleons total in its nucleus. It decays by emitting an
alpha
Ans:
234U92
ΰ
230Th90 + a
Choice (C) 31. Ka
and Kb
x-rays are emitted when there is a transition of
electron
Ans: K
series end in n = 1 Choice (A) 32. A certain
radioactive material ZXA starts emitting a
and b
particles successively such that the end product
Ans:
ZXA
ΰ
Z-
3YA-
8 + 2a
+ 1b
Choice (B) 33. In the circuit
shown above, an input of 1 V is fed into the inverting input of an ideal Op-amp
A. The output signal
Ans:
Choice (B) 34. When a solid
with a band gap has a donor level just below its empty energy band, -
Ans: Knowledge
based Choice (D) 35. A p n
junction has acceptor impurity concentration of 1017 cm-
3 in the P
side and donor impurity concentration of 1016 cm-
3 in the N
side. What is the contact potential at the
Ans: V
contact
=
Choice (A) 36. A zener diode
has a contact potential of 1 V in the absence of biasing. It undergoes zener
breakdown for an electric field of 106 V/m at the depletion region
of p-n junction. If the width
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is enclosed by a hollow sphere of 
= 450
. What should be the electric potential 
of the initial value in 2 hours. The half 
= 