Question

urgent urgent urgent urgent urgent
answer the following correctly
1. least count of ammeter
2. how can you say repulsion is the sure rtest of magnetism

Answer 1

Least count of any instrument is the smallest division you can measure using the instrument. An ammeter may have one or multiple ranges. Select a range you wish to check. Let us say it is 500 mA range, and has 50 markings from 0 to full scale.

Answer 2

1.
Least count =
$\frac{value \: of \: one \: main \: scale \: division}{total \: number \: of \: scale \: division}$


2.
Attraction can be caused either by opposite poles of magnets or between one pole of magnet and an unmagneted bar of iron whereas repulsion is possible between the two similar poles of magnets. Hence, repulsion is the surest test of magnetism.