2019-03-01_Physics_Times

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[ONLINE QUESTIONS]






[2017]





[2017]





[2017]

The energy stored in the electric field produced by
a metal sphere is 4.5 J. If the sphere contains 4 C
charge, its radius will be:
(a) 32 mm (b) 16mm (c) 28 mm (d) 20 mm
There is a uniform electrostatic field in a region.The
potential at various points on a small sphere centred
at p, in the region, is found to vary between in
limits 589.0V to 589.8V. What is the potential at a
point on the sphere whose radius vector makes an
angle of 600 with the direction of the field?
(a) 589.4 V (b) 589.5 V (c) 589.2 (d) 589.6 V
Four closed surfaces and corresponding charge
distributions are shown below. Let the respective
electric fluxes through the surfaces be    1 , , , 2 3
and  4. Then.

ELECTRO STATICS

(a)        1 2 3 4 (b)        1 2 3 4
(c)       1 3 ; 2 4 (d) 1 2 3 4
The potential (in volts) of a charge distribution is
given by

      

V(z) 30 5z^2 for | z | 1m
V(z) 35 10 | z | for | z | 1m
V(z) does not depend on x and y. If this potential is
generated by a constant charge per unit volume
, (in units of ) which is spread over certain
region, then choose the correct statement.

(a)    (^40)  in the entire region.
(b)   (^20)  in the entire region.
(c)    (^20)  for |z|1m and   0 else where.
(d)    (^10)  for |z| 1m and   0 else where.
A wire of length L(= 20 cm), is bent into a
semicircular arc. If the two equal halves of the arc
were each to be uniformly charged with charges
Q,[ Q 10^3  0 Coulomb where  0 is the
permittivity(in SI units) of free space] the net electric
field at the centre O of the semicircular arc would
be:
4.
[2016]
5.
[2015]

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