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प्रश्न
State the condition at which we say the two coils kept close to each other are perfectly coupled with each other.
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उत्तर
When the coefficient of coupling (K) is 1, then the two coils kept close to each other are said to be perfectly coupled with each other.
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संबंधित प्रश्न
Electric field intensity in free space at a distance ‘r’ outside the charged conducting sphere of radius ‘R’ in terms of surface charge density ‘ a ’ is............................
(a)`sigma / in_0[R/r]^2`
(b)`in_0/sigma[R/r]^2`
(c)`R/r[sigma/in_0]^2`
(d)`R/sigma[r/in_0]^2`
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- longer side,
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(d) steel
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Consider the energy density in a solenoid at its centre and that near its ends. Which of the two is greater?
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(b) The charge on C long after t = 0 is εC.
(c) The current in L just before t = t0 is ε/R.
(d) The current in L long after t = t0 is ε/R.
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State the principles of the electric motor and electric generator.
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List two ways of increasing the strength of an electromagnet if the material of the electromagnet is fixed.
Draw a labelled diagram to make an electromagnet from a soft iron bar. Mark the polarity at its ends in your diagram. What precaution would you observe while making it?
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- State four ways of increasing the magnitude of force acting on the coil.
Observe the given figure of Fleming’s Right Hand Rule and write the labels of A and B correctly.

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