how will we predict the direction of induced current in different situtions as given in question no. 1 of ncert chapter6?
According to Lenz’s law the emf developed will oppose the source of change, thus to oppose the approaching of the south pole of the magnet a south pole will be developed at the end of the coil. Thus current will flow in the clockwise direction. Thus the direction of the induced current is along qrpq.
According to Lenz’s law the emf developed will oppose the source of change, thus to oppose the approaching of the south pole of the magnet a south pole will be developed at the end of the first coil. In the second coil as the north pole is moving away a south pole again would be developed to oppose this movement. Thus current will flow in the clockwise direction in both coils. Thus the direction of the induced current in first coil is along qrpq. In the 2nd coil it will flow in xyzx direction.
According to Lenz’s law the emf developed will oppose the source of change, In the first loop with closing of the key the current in it increases, with increase in current the strength of the magnetic south pole will also increase at the end of the 1st loop. In the 2nd loop to oppose the increasing of the magnetic field a south pole is developed in it. The direction of the induced current is along yzxy.
The current in the loop with current is increased using the rheostat and north pole is developed in the current carrying loop, strength of the north pole increases with increase in current in the ckt. In the 2nd closed loop a North Pole will be developed to oppose the increasing north pole strength. Thus current will flow in it in anti-clockwise direction along zyxz direction.
As the tapping key is released the strength of the North Pole decreases in the first loop, the 2nd coil will tend to oppose this decrease in North Pole strength thus current in the 2nd coil will flow in such a way that a south pole is developed at the 2nd coil. Thus current will flow in the direction xryx.
No current is induced in the loop because the magnetic flux is perpendicular with the area vector of the loop.