NCERT Solutions
Board Paper Solutions
Ask & Answer
School Talk
Login
GET APP
Login
Create Account
Popular
Latest
Expert Answers
ALL
Raj Aryan
Subject: Physics
, asked on 17/5/18
Q).
This side is extended to infinity. Now what will be the value of electric flux due to charge q.
(Answer:
$\frac{q}{24{\epsilon}_{0}}$
Answer
1
Shivansh Ahuja
Subject: Physics
, asked on 16/5/18
Two concentric spheres are given equal amount of charge of the same nature then which may have higher potential
Answer
1
Shivansh Ahuja
Subject: Physics
, asked on 16/5/18
Two short dipoles each of dipole moment p are placed at origin. The dipole moment of one dipole is along x axis and other is along y axis. The magnitude of electric field at a point (a,0)is given by
Answer
2
Kabir Chhabra
Subject: Physics
, asked on 16/5/18
1) In the diagram shown the charge + Q is fixed. Another charge + 2q and mass M is projected from a distance R from the fixed charge. Minimum septation between the two charges if the velocity becomes
$\frac{1}{\sqrt{3}}$
times of the projected velocity, at this moment is. (Assume gravity to be absent)
$\left(a\right)\frac{\sqrt{3}}{2}R\phantom{\rule{0ex}{0ex}}\left(b\right)\frac{1}{\sqrt{3}}R\phantom{\rule{0ex}{0ex}}\left(c\right)\frac{1}{2}R\phantom{\rule{0ex}{0ex}}\left(d\right)Noneofthese$
Answer
1
Kabir Chhabra
Subject: Physics
, asked on 16/5/18
Q38
38.
A point charge Q is located on the axis of a disc of radius R at a distance b from the plane of the disc (figure). Show that if one-fourth of the electric flux from the charge passes through the disc, then R=
$\sqrt{3}$
b.
Answer
1
Deepika Walia
Subject: Physics
, asked on 15/5/18
Solve this:
Q. In a certain region of space, variation of potential with distance from origin as we move along x-axis is given by V = 8
${x}^{2}$
+ 2, where x is the x-coordinate of a point in space. The magnitude of electric field at a point (- 4, 0) is
(1) - 16 V/m
(2) 16 V/m
(3) - 64 V/m
(4) 64 V/m
Answer
1
Deepika Walia
Subject: Physics
, asked on 15/5/18
Solve this:
Q. Six point charges are placed at the vertices of a regular hexagon of side a as shown. If E represents electric field and V represents electric potential at O, then
(1) E = 0 but V
$\ne $
0
(2) E
$\ne $
0 but V = 0
(3) E = 0 and V = 0
(4) E
$\ne $
0 and V
$\ne $
0
Answer
2
Deepika Walia
Subject: Physics
, asked on 15/5/18
Solve this:
Q3. Electric potential in a region is varying according to the relation V =
$\frac{3{\mathrm{x}}^{2}}{2}-\frac{{\mathrm{y}}^{2}}{4}$
, where x and y are in metre and V is in volt. Electric field intensity (in N/C) at a point (1 m, 2 m) is
(1) 3
$\hat{\mathrm{i}}$
–
$\hat{\mathrm{j}}$
(2) –3
$\hat{\mathrm{i}}$
+
$\hat{\mathrm{j}}$
(3) 6
$\hat{\mathrm{i}}$
– 2
$\hat{\mathrm{j}}$
(4) – 6
$\hat{\mathrm{i}}$
+ 2
$\hat{\mathrm{j}}$
Answer
1
Deepika Walia
Subject: Physics
, asked on 15/5/18
Solve this:
6. Electric charges having some magnitude of electric charge 'q' coulombs are placed at x=1 m, 2 m, 4 m, 8m..... so on. If any two consecutive charges have opposite sign but the first charge is necessarily positive, what will be the potential at x=0 ?
$\left(1\right)\mathrm{Infinity}\left(2\right)\mathrm{Zero}\phantom{\rule{0ex}{0ex}}\left(3\right)\frac{1}{4{\mathrm{\pi \epsilon}}_{0}}\left(\frac{2\mathrm{q}}{3}\right)\left(4\right)\frac{1}{4{\mathrm{\pi \epsilon}}_{0}}\left(2\mathrm{q}\right)$
Answer
1
Deepika Walia
Subject: Physics
, asked on 15/5/18
Solve this:
Q.28. Calculate the work done in taking a charge - 2
$\times {10}^{-9}$
C from A to B via C (in diagram)
(1) 0.2 joule
(2) 1.2 joule
(3) 2.2 joule
(4) zero
Answer
1
Deepika Walia
Subject: Physics
, asked on 15/5/18
Solve this:
Q.24. Three charges - q, Q and - q are placed respectively at equal distances on a straight line. If the potential energy of the system of three charges is zero, then what is the ratio of Q : q?
(1) 1 : 1
(2) 1 : 2
(3) 1 : 3
(4) 1 : 4
Answer
1
Deepika Walia
Subject: Physics
, asked on 15/5/18
Solve this:
Q17. Determine the electric field strength vector if the potential of this field depends on x, y coordinates as V = 10 axy
(1) 10 a (y
$\hat{\mathrm{i}}$
+ x
$\hat{\mathrm{j}}$
) (2) – 10 a [y
$\hat{\mathrm{i}}$
+ x
$\hat{\mathrm{j}}$
]
(3) – a [y
$\hat{\mathrm{i}}$
+ x
$\hat{\mathrm{j}}$
] (4) –10 a [x
$\hat{\mathrm{i}}$
+ y
$\hat{\mathrm{k}}$
]
Answer
1
Deepika Walia
Subject: Physics
, asked on 15/5/18
Solve this:
Q. An electric dipole of length 2 cm is placed with its axis making an angle of 30
$\xb0$
to a uniform electric field
${10}^{5}$
N/C. If it experiences a torque of
$10\sqrt{3}$
Nm, then potential energy of the dipole
(1) - 10 J
(2) - 20 J
(3) - 30 J
(4) - 40 J
Answer
1
Deepika Walia
Subject: Physics
, asked on 15/5/18
$Achargeof10\mu Cisplacedattheorigionofx-ycoordinatesystem.Thepotentialdifferencebetweentwopoints\left(0,a\right)and\left(a,0\right)involtswillbe\phantom{\rule{0ex}{0ex}}\left(1\right)\frac{9\times {10}^{4}}{a}\phantom{\rule{0ex}{0ex}}\left(2\right)\frac{9\times {10}^{4}}{a\sqrt{2}}\phantom{\rule{0ex}{0ex}}\left(3\right)\frac{9\times {10}^{4}}{2a}\phantom{\rule{0ex}{0ex}}\left(4\right)zero$
Answer
4
Deepika Walia
Subject: Physics
, asked on 15/5/18
Solve this: Three isolated equal charges are placed at the three corners of an equilateral triangle as shown in figure. The statement which is true for net electric potential V and net electric field intensity E at the centre of the triangle is
$1.E=0,V=0\phantom{\rule{0ex}{0ex}}2.V=0,E\ne 0\phantom{\rule{0ex}{0ex}}3.E=0,V\ne 0\phantom{\rule{0ex}{0ex}}4.E\ne 0,V\ne 0$
Answer
1
Prev
1
2
3
4
5
Next
What are you looking for?

(Answer: $\frac{q}{24{\epsilon}_{0}}$

$\left(a\right)\frac{\sqrt{3}}{2}R\phantom{\rule{0ex}{0ex}}\left(b\right)\frac{1}{\sqrt{3}}R\phantom{\rule{0ex}{0ex}}\left(c\right)\frac{1}{2}R\phantom{\rule{0ex}{0ex}}\left(d\right)Noneofthese$

38.A point charge Q is located on the axis of a disc of radius R at a distance b from the plane of the disc (figure). Show that if one-fourth of the electric flux from the charge passes through the disc, then R= $\sqrt{3}$ b.Q. In a certain region of space, variation of potential with distance from origin as we move along x-axis is given by V = 8${x}^{2}$ + 2, where x is the x-coordinate of a point in space. The magnitude of electric field at a point (- 4, 0) is

(1) - 16 V/m

(2) 16 V/m

(3) - 64 V/m

(4) 64 V/m

Q. Six point charges are placed at the vertices of a regular hexagon of side a as shown. If E represents electric field and V represents electric potential at O, then

(1) E = 0 but V$\ne $0

(2) E $\ne $ 0 but V = 0

(3) E = 0 and V = 0

(4) E$\ne $ 0 and V$\ne $0

Q3. Electric potential in a region is varying according to the relation V = $\frac{3{\mathrm{x}}^{2}}{2}-\frac{{\mathrm{y}}^{2}}{4}$, where x and y are in metre and V is in volt. Electric field intensity (in N/C) at a point (1 m, 2 m) is

(1) 3$\hat{\mathrm{i}}$– $\hat{\mathrm{j}}$ (2) –3$\hat{\mathrm{i}}$+ $\hat{\mathrm{j}}$

(3) 6$\hat{\mathrm{i}}$– 2$\hat{\mathrm{j}}$ (4) – 6 $\hat{\mathrm{i}}$+ 2$\hat{\mathrm{j}}$

6. Electric charges having some magnitude of electric charge 'q' coulombs are placed at x=1 m, 2 m, 4 m, 8m..... so on. If any two consecutive charges have opposite sign but the first charge is necessarily positive, what will be the potential at x=0 ?

$\left(1\right)\mathrm{Infinity}\left(2\right)\mathrm{Zero}\phantom{\rule{0ex}{0ex}}\left(3\right)\frac{1}{4{\mathrm{\pi \epsilon}}_{0}}\left(\frac{2\mathrm{q}}{3}\right)\left(4\right)\frac{1}{4{\mathrm{\pi \epsilon}}_{0}}\left(2\mathrm{q}\right)$

Q.28. Calculate the work done in taking a charge - 2$\times {10}^{-9}$ C from A to B via C (in diagram)

(1) 0.2 joule

(2) 1.2 joule

(3) 2.2 joule

(4) zero

Q.24. Three charges - q, Q and - q are placed respectively at equal distances on a straight line. If the potential energy of the system of three charges is zero, then what is the ratio of Q : q?

(1) 1 : 1

(2) 1 : 2

(3) 1 : 3

(4) 1 : 4

Q17. Determine the electric field strength vector if the potential of this field depends on x, y coordinates as V = 10 axy

(1) 10 a (y$\hat{\mathrm{i}}$ + x$\hat{\mathrm{j}}$) (2) – 10 a [y$\hat{\mathrm{i}}$ + x$\hat{\mathrm{j}}$]

(3) – a [y$\hat{\mathrm{i}}$ + x$\hat{\mathrm{j}}$] (4) –10 a [x$\hat{\mathrm{i}}$ + y$\hat{\mathrm{k}}$]

Q. An electric dipole of length 2 cm is placed with its axis making an angle of 30$\xb0$ to a uniform electric field ${10}^{5}$ N/C. If it experiences a torque of $10\sqrt{3}$ Nm, then potential energy of the dipole

(1) - 10 J

(2) - 20 J

(3) - 30 J

(4) - 40 J

$1.E=0,V=0\phantom{\rule{0ex}{0ex}}2.V=0,E\ne 0\phantom{\rule{0ex}{0ex}}3.E=0,V\ne 0\phantom{\rule{0ex}{0ex}}4.E\ne 0,V\ne 0$