MHT CET202415 May 2024Morning ShiftPhysicsAlternating CurrentActual
When a coil is connected to a d.c. source of e.m.f. 12 volt, then the current of 4 A flows in it. If the same coil is connected to a 12 volt, 50 Hz a.c. source, then the current flowing in it is 2.4 A . Then self-inductance of the coil will be
Options
- A48 H
- B12 H
- C4 10⁻² H
- D8 10⁻² H
Correct answer
C. 4 10⁻² H
Step-by-step solution
array ll & R = V I = 12 4 =3 ( d.c. source ) & Z = 12 2.4 =5 ( a.c. source ) & Z ^2= R ^2+ X _ L ^2 & X _ L ^2=25-9=16 & X _ L =4 & Also, X_L= L =2 fL & L = X_L 2 f = 4 2 50 = 4 100 = 4 10⁻² H array