42 A straight wire of a diameter 0 5 mm carrying a current

Last updated: 6/3/2023

42 A straight wire of a diameter 0 5 mm carrying a current of 1 A is replaced by another wire of 1 mm diameter carrying the same current The strength of the magnetic field far away is 1 One quarter of the earlier value 2 No change 3 Twice the earlier value 4 One half of the earlier value