Question

in many of the activitities in this chapter we have used a tester made up of LED can we avoid LED and use some thing else as a tester magnetic compass needle could be an alternative tester we know that when we take a current carrying wire near magnetic compass needle it shows deflection use this property to make a tester of magnetic compass needle you may refer to the following figure

Answer 1

we can also use a magnetic compass needle also as even if very small current flows in a wire , a compass needle kept nearby gets deflected, as a magnetic field is produced around it.