Solenoid Long With Inner Diameter Three Layers Windings 1000 Turns Each Carries Current

A solenoid of 1.5 m long with inner diameter of 4 cm has three layers of windings of 1000 turns each & carries a … 2.1 …

Answers:

The correct option (b) 6.31 × 10–6 wb

 Explanation:

 L = 1.5 m

 I = 2A

Total number of turns = 3 × 1000 = 3000

∴ Turns per unit meter = n = [(3000) / (1.5)] = 2000

 r = [(4 cm)/2] = 2 × 10–2 m

As   ɸ = AB cos θ = AB cos 0

 ɸ = AB

put B = μonI & A = πr2 we get

 ɸ = π r2 × μonI = π × (2 × 10–2)2 × 4π × 10–7 × 2000 × 2

∴   θ = 6.31 × 10–6wb