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Aparna Sahu
Subject: Physics
, asked on 24/2/18
The magnetic field in a travelling electromagnetic wave has a peak value of 20 nT. The peak value of
electric field strength is :
(A) 3 V/m (B) 6 V/m (C) 9 V/m (D) 12 V/m
Answer
1
Sofiya Parihar
Subject: Physics
, asked on 24/2/18
Answer the third and fourth part of question no.28
Q.28. (iii) Derive the expression for maximum value of the induced emf and state the induced emf and state the rule that gives the direction of the induced emf.
(iv) Show the variation of the emf generated versus time as the armature is rotated with respect to the direction of the magnetic fields.
Answer
1
Mitali
Subject: Physics
, asked on 23/2/18
Please give the solution
Q.27. A magnetic field B is confined to a region
$r\le a$
and points out of the paper (the z-axis), r = 0 being the centre of the circular region. A charged ring (charge = Q) of radius b, b > a and mass m lies in the x-y plane with its centre at the origin. The ring is free to rotate and is at rest. The magnetic field is brought to zero in time
$\u2206$
t. Find the angular velocity
$\omega $
of the ring after the field vanishes.
Answer
1
Megha Prasadan
Subject: Physics
, asked on 23/2/18
Explain this question with app reasoning pls!
Question 1
In the diagram below is shown a circular loop carrying current I. Show the direction of the magnetic field with the help of lines of force.
Answer
1
Shobhit De
Subject: Physics
, asked on 23/2/18
Q 10.
A bar magnet is moved in the direction indicated by the arrow between two coils PQ and CD. Predict the directions of induced current in each coil.
Answer
1
Aparna Sahu
Subject: Physics
, asked on 22/2/18
Solve this.
Q. A current i = 2 sin (
$\mathrm{\pi t}/3$
) amp is flowing in an inductor of 2 henry. The amount of work done in increasing the current from 1.0 amp to 2.0 amp is
Solve this.
Answer
1
Megha Prasadan
Subject: Physics
, asked on 22/2/18
No link pls
can we use the formula B*w*r^2/2
Q.8. A wheel with 8 metallic spokes each 50 cm long is rotated with a speed of 120 rev/min in a plane normal to the horizontal component of the earth's magnetic field. The earth's magnetic field at the place is 0.4 G and the angle of dip is 60
$\xb0$
. Calculate the emf induced between the axle and the rim of the wheel. How will the value of emf be affected if the number of spokes were increased ?
Answer
1
Aparna Sahu
Subject: Physics
, asked on 19/2/18
Solve this.
Q). A conductor of length 1 m moves with a velocity of 50
$m{s}^{-1}$
at an angle of 30
$\xb0$
to the direction of a uniform magnetic field of flux density 1.5
$Wb{m}^{-2}$
. What is the e.m.f induced in the conductor?
Answer
1
Aparna Sahu
Subject: Physics
, asked on 18/2/18
$13.Whatisthereluc\mathrm{tan}ceofamaterialthathasalengthof0.07m,across-sectionalareaof0.014{m}^{2},andapermeabilityof4,500Wb/Atxm?\phantom{\rule{0ex}{0ex}}\phantom{\rule{0ex}{0ex}}\left(1\right)111At/Wb\phantom{\rule{0ex}{0ex}}\left(2\right)11At/Wb\phantom{\rule{0ex}{0ex}}\left(3\right)0.001111At/Wb\phantom{\rule{0ex}{0ex}}\left(4\right)1At/Wb$
Answer
1
Archana
Subject: Physics
, asked on 18/2/18
Answer this
Dont give any linkss
Q. Derive an expression for the instantaneous value of emf induced in the coil. Why is the emf is maximum when the plane of the armature is parallel to the magnetic field?
Answer
1
Tanaya
Subject: Physics
, asked on 13/2/18
Ques 4
4. The electric current flowing in a wire in the direction from P to Q is
decreasing. Find out the direction of the induced current in the metallic
loop kept beside the wire as shown. Give reason
Answer
2
Ayushi Aggarwal
Subject: Physics
, asked on 5/2/18
why is induced electric fields due to changing magnetic flux more readily observable than the induced magnetic fields due to changing electric fields ?
Answer
1
Kshitij Gaur
Subject: Physics
, asked on 5/2/18
Solve and don't give any links
Q.8. Starting from the expression for the energy W =
$\raisebox{1ex}{$1$}\!\left/ \!\raisebox{-1ex}{$2$}\right.L{I}^{2}$
, stored in a solenoid of self-inductance L to build up the current I, obtain the expression for the magnetic energy in terms of the magnetic field B, area A and length l of the solenoid having n number of turns per unit length.
Hence, show that the energy density is given by
$\frac{{B}^{2}}{2{\mu}_{0}}$
.
Answer
1
Archana
Subject: Physics
, asked on 5/2/18
What is the source of energy generation in this AC Generator?
*don't give any links*
Answer
1
Ayushi Aggarwal
Subject: Physics
, asked on 3/2/18
An iron disc is rotating in the direction (as shown in the given figure)
A magnetic field applied to the disc at the bottom of the rotating wheel such that the position of the applied field does not change as the disc rotates. In regions P and Q draw the direction Of the induced current so produced .
Answer
1
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What are you looking for?

electric field strength is :

(A) 3 V/m (B) 6 V/m (C) 9 V/m (D) 12 V/m

Q.28. (iii) Derive the expression for maximum value of the induced emf and state the induced emf and state the rule that gives the direction of the induced emf.

(iv) Show the variation of the emf generated versus time as the armature is rotated with respect to the direction of the magnetic fields.

Q.27. A magnetic field B is confined to a region $r\le a$ and points out of the paper (the z-axis), r = 0 being the centre of the circular region. A charged ring (charge = Q) of radius b, b > a and mass m lies in the x-y plane with its centre at the origin. The ring is free to rotate and is at rest. The magnetic field is brought to zero in time $\u2206$t. Find the angular velocity $\omega $ of the ring after the field vanishes.

Question 1

In the diagram below is shown a circular loop carrying current I. Show the direction of the magnetic field with the help of lines of force.

Q 10.A bar magnet is moved in the direction indicated by the arrow between two coils PQ and CD. Predict the directions of induced current in each coil.Q. A current i = 2 sin ( $\mathrm{\pi t}/3$) amp is flowing in an inductor of 2 henry. The amount of work done in increasing the current from 1.0 amp to 2.0 amp is Solve this.

can we use the formula B*w*r^2/2

Q.8. A wheel with 8 metallic spokes each 50 cm long is rotated with a speed of 120 rev/min in a plane normal to the horizontal component of the earth's magnetic field. The earth's magnetic field at the place is 0.4 G and the angle of dip is 60$\xb0$. Calculate the emf induced between the axle and the rim of the wheel. How will the value of emf be affected if the number of spokes were increased ?

Q). A conductor of length 1 m moves with a velocity of 50 $m{s}^{-1}$ at an angle of 30$\xb0$ to the direction of a uniform magnetic field of flux density 1.5 $Wb{m}^{-2}$. What is the e.m.f induced in the conductor?

Dont give any linkss

Q. Derive an expression for the instantaneous value of emf induced in the coil. Why is the emf is maximum when the plane of the armature is parallel to the magnetic field?

4. The electric current flowing in a wire in the direction from P to Q is

decreasing. Find out the direction of the induced current in the metallic

loop kept beside the wire as shown. Give reason

Q.8. Starting from the expression for the energy W = $\raisebox{1ex}{$1$}\!\left/ \!\raisebox{-1ex}{$2$}\right.L{I}^{2}$, stored in a solenoid of self-inductance L to build up the current I, obtain the expression for the magnetic energy in terms of the magnetic field B, area A and length l of the solenoid having n number of turns per unit length.

Hence, show that the energy density is given by $\frac{{B}^{2}}{2{\mu}_{0}}$.

What is the source of energy generation in this AC Generator?

*don't give any links*

A magnetic field applied to the disc at the bottom of the rotating wheel such that the position of the applied field does not change as the disc rotates. In regions P and Q draw the direction Of the induced current so produced .