The figure depicts a cross-section of a large metal sheet with an electric current flowing along its surface. The current in a dl-width strip is (Kdl), where K is a constant. What is the magnetic field at a point P and at a distance x from the metal strips?
1.
2.
3.
4.
1. 0.25 amp
2. 0.8 amp
3. 0.2 amp
4. 0.5 amp
The current sensitivity of a moving coil galvanometer is 5 div/mA and its voltage sensitivity (angular deflection per unit voltage applied) is 20 div/V. How much is the resistance of the galvanometer?
1. | \(40~ \Omega\) | 2. | \(25~ \Omega\) |
3. | \(250~ \Omega\) | 4. | \(500~ \Omega\) |
Perpendicularly, an electron and a proton enter a magnetic field. Both have the same amount of kinetic energy. Which of the following statements is correct?
1. | Trajectory of electron is less curved |
2. | Trajectory of proton is less curved |
3. | Both trajectories are equally curved |
4. | Both move on a straight-line path |
A particle having a mass of carries a charge of The particle is given an initial horizontal velocity of in the presence of an electric field and magnetic field . How can we keep the particles moving in a horizontal direction?
a. | should be perpendicular to the direction of velocity and should be along the direction of velocity. |
b. | Both and should be along the direction of velocity. |
c. | Both and are mutually perpendicular and perpendicular to the direction of velocity. |
d. | should be along the direction of velocity and should be perpendicular to the direction of velocity. |
Which one of the following pairs of statements are possible?
1. a and c
2. c and d
3. b and c
4. b and d
A long solenoid has 800 turns per metre of the length of the solenoid. A current of 1.6 A flows through it. What is the magnetic induction at the end of the solenoid on its axis?
1. | \(16 \times 10^{-4}~\mathrm T\) | 2. | \(8 \times 10^{-4}~\mathrm T\) |
3. | \(32 \times 10^{-4}~\mathrm T\) | 4. | \(4 \times 10^{-4}~\mathrm T\) |
A cell is connected between the points A and C of a circular conductor ABCD of centre O with an angle of AOC = 60°.
If B1 and B2 are the magnitudes of the magnetic fields at O due to the currents in ABC and ADC respectively, the ratio B1: B2 will be:
1. 0.2
2. 6
3. 1
4. 5
What is the result of an electric charge in uniform motion?
1. | an electric field only. |
2. | a magnetic field only. |
3. | both electric and magnetic field. |
4. | neither electric nor magnetic field. |
Two particles each of mass m and charge q are attached to the two ends of a light rigid rod of length 2R. The rod is rotated at constant angular speed about a perpendicular axis passing through its centre. What is the ratio of the magnitudes of the magnetic moment of the system and its angular momentum about the centre of the rod?
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2.
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4.
By which relation is the deflection of the coil θ related to the electrical current i in a moving coil galvanometer?
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