Solenoids is used common used as electromagnets. It is also used in electromagnetic induction to show Faraday’s law and Lenz’s law. For inner solenoid, internal diameter is approximately 13 mm and external diameter is approximately 22 mm. For outer solenoid, internal diameter is approximately 35 mm and external diameter is approximately 49 mm. Number of turns on inner solenoid and outer solenoid are 400 and 1150 respectively.