Induced Current The figures below show two different situations where a current
ID: 1640498 • Letter: I
Question
Induced Current The figures below show two different situations where a current may be induced in a loop according to Faraday's Law, with the direction given by Lenz' Law. The magnetic field strength in Figure 2 is represented by the density of crosses. Select true or false for the current in the loop. The cardinal directions are as defined in the compass rose. B field points into page I NW NE ES NI SE Fig. 1 Fig. 2. Fig 2: Loop moving East, n induced current o Fig 1: Magnet moving West, induced current 'b' Fig 2: Loop moving West, induced current 'b' Fig 2: Loop moving South, induced current 'b'. Fig 1: Magnet moving East, induced current 'b' Fig 1: Loop moving West, induced current 'b'.Explanation / Answer
1. This is true as there is no associated change in magnetic flux through the loop.
2.Yes, is true. When the magnet moves through the west, the magnetic flux increases in the loop. Hence according to Lenz's law it will try to oppose this change. Thus it will produce its own magnetic field in the opposite direction.
3.False. No change in magnetic flux. Hence induced emf is zero.
4. The magnetic field lines become less dense as the loop moves towards the south. So the magnetic flux through the loop decreases. So it will try to oppose this decrease and produce field of its own in the direction of decrease ie into the screen. hence b is correct.
5.False. it will be a.
6.Loop moving west is equivalent to magnet moving east. So it is false. The direction will be a.