A long solenoid carrying a current produces a magnetic field \(B\) along its axis. If the current is doubled and the number of turns per cm is halved, then the new value of the magnetic field will be equal to:
1. \(B\)
2. \(2B\)
3. \(4B\)
4. \(\dfrac B 2\)
Subtopic:  Ampere Circuital Law |
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An infinitely long hollow conducting cylinder with radius \(R\) carries a uniform current along its surface. The correct representation of magnetic field (\(B\)) as a function of radial distance (\(r\)) from the axis of the cylinder is:
1. 2.
3. 4.
Subtopic:  Ampere Circuital Law |
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Given below are two statements :
Statement I: When currents vary with time, Newton's third law is valid only if momentum carried by the electromagnetic field is taken into account.
Statement II: Ampere's circuital law does not depend on Biot-Savart's law.

In the light of the above statements, choose the correct answer from the options given below: 
1. Both Statement I and Statement II are false
2. Statement I is false, but Statement II is true.
3. Both Statement I and Statement II are true.
4. Statement I is true, but Statement II is false.

 
Subtopic:  Ampere Circuital Law |
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