Class 12th Physics 2017 Set1 Delhi Board Paper Solution
Obtain the expression for the mutual inductance of two long co-axial solenoids S1 and S2 wound one over the other, each of length L and radii r1 and r2 and n1 and n2 , number of turns per unit length, when a current I is set up in the outer solenoid S2 .
Magnetic field B formed along the axis of outer solenoid.
B = µ0n2I.
Flux linked with inner solenoid S1 per turn.
= B.A = π r21B = × π r21 x µ0 n2 I
Flux linked with whole of inner solenoid having total no of turns n1 L
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A point charge +10 μC is a distance 5 cm directly above the centre of a square of side 10 cm, as shown in Fig. 1.34. What is the magnitude of the electric flux through the square? (Hint: Think of the square as one face of a cube with edge 10 cm.)
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A point charge of 2.0 μC is at the centre of a cubic Gaussian surface 9.0 cm on edge. What is the net electric flux through the surface?
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