Year: 2022
Topic: Magnetism and matter
Time :
1.
A long solenoid of radius 1mm has 100 turns per mm. If 1 A current flows in the solenoid, the magnetic field strength at the centre of the solenoid is
(1). \(6.28 \times 10^{−2}\,T\)
(2). \(12.56 \times 10^{−2}\,T\)
(3). \(12.56 \times 10^{−4}\,T\)
(4). \(6.28 \times 10^{−4}\,T\)