Physics
The diagram, shows a fixed coil of several turns connected to a centre zero galvanometer G and a magnet NS which can move in the direction shown in the diagram.
(a) Describe the observation in the galvanometer if (i) the magnet is moved rapidly, (ii) the magnet is kept stationary after it has moved into the coil, (iii) the magnet is then rapidly pulled out of the coil.
(b) How would the observation in (i) of part (a) change if a more powerful magnet is used?
Answer
(a) (i) A deflection is observed in the galvanometer towards the right when the magnet is moved away rapidly.
(ii) The deflection becomes zero, when the magnet is kept stationary after it has moved into the coil.
(iii) The deflection again occurs in opposite direction, when the magnet is rapidly pulled out of the coil.
(b) When a more powerful magnet is used then the deflection is increased.
Related Questions
The diagram shows a coil of several turns of copper wire near a magnet NS. The coil is moved in the direction of arrow shown in the diagram.
(i) In what direction does the induced current flow in the coil?
(ii) Name the law used to arrive at the conclusion in part (i).
(iii) How would the current in coil be altered if:
- the coil has twice the number of turns,
- the coil was made to move three times fast?
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