School of Physics
University of Hyderabad
Minor examination โ 2
Electromagnetic Theory โ I (PH403)
Date: 21/1/2022 Total Marks: 25 Time: 1.30 hour
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(1-8 , each question carry 1 mark)
1. Find the dipole moment of the system.
(a) 3qa๐ง๎ธ (b) 2qa๐ง๎ธ (c) 3qa๐ฆ๏ (d) 2qa๐ฆ๏
2. Given the field ๐ธ
๓ฐ
= -(6x๐ฅ๏ +8y๐ฆ๏ ) . Then find the energy stored in the volume
described by 0 โค x โค 1, 0 โค y โค 1, 0 โค z โค 1m.
a) 45๐0
3๐ฝ (b) 50๐0
3๐ฝ (c) 55๐0
3๐ฝ (d) 40๐0
3๐ฝ
3. Consider axially symmetric static charge distribution of the form, ๏ฒ=๏ฒ0 (๐0
๐)2
๐โ( ๐
๐0) cos2๏ฆ. The radial component of the dipole moment due to this charge
distribution is -----------------
(a) 2๏ฐ๏ฒ0 r0 4 (b) ๏ฐ๏ฒ0 r0 4 (c)3๏ฐ๏ฒ0 r0 4 (d) 4๏ฐ๏ฒ0 r0 4
4. Consider a dielectric sphere of radius R with polarization ๐
๓ฐ
= ๐
๐2 ๐๎ธ. find ๏ณb and ๏ฒb
(a) ๐
๐
2 , -4k๏ฐ๏ค3(r) (b) ๐
๐
2 , -3k๏ฐ๏ค3(r) (c)โ ๐
๐
2 , -4k๏ฐ๏ค3(r) (d) ๐
๐
2 , 4k๏ฐ๏ค3(r)
5. The magnitude of intensity of electric filed at a distance x on axial line and at a
distance y on equatorial line on a given dipole are equal, then x:y is
(a) 1:1 (b) 1:โ2 (c) 1:2 (d) โ2
3 : 1
6. The distance between H+ and Cl- ions in HCl molecule is 1.28 ร
. What will be
the potential due to this dipole at a distance of 12ร
on the axis of dipole
(a) 0.13 V (b) 1.3 V (c) 13 V (d) 130 V
3q
-q
a
z
y
x
