Field inside a solenoid is A Directly proportional to the current flowing through the coil B Directly proportional to its length C Inversely porportional to total number of turns. D Inversely proportional to current.

The magnetic field inside a solenoid is:

A. Directly proportional to the current flowing through the coil: This is true. According to Ampere's law, the magnetic field inside a solenoid is directly proportional to the current flowing through it. If the current increases, the magnetic field increases and vice versa.

B. Directly proportional to its length: This is false. The magnetic field inside a solenoid is inversely proportional to its length. This means that as the length of the solenoid increases, the magnetic field decreases and vice versa.

C. Inversely proportional to the total number of turns: This is false. The magnetic field inside a solenoid is directly proportional to the total number of turns. This means that as the number of turns increases, the magnetic field also increases and vice versa.

D. Inversely proportional to current: This is false. As mentioned in point A, the magnetic field inside a solenoid is directly proportional to the current flowing through it. If the current increases, the magnetic field increases and vice versa.