Question

a solenoid of 1 metre long and 4 centimeter in diameter possess 10 turns per centimeter current of a 5 ampere is flowing through it calculate a magnetic induction inside it and at one end of axis of a solenoid

Answer 1

B= 4π * 10^-7 * N * i / l
B = 4π *10^-7 *10*5 /1
B = 200π*10^-7
B = 2π*10^-5 N/A-m