ELECTROMAGNETIC INDUCTION

1.       Energy stored in an inductor is:

• 1/2 LI²

• 1/2 CV²

• 1/3 LI²

• 1/2 L²I²

Resistance opposes current, inductor opposes

• Current

• Change in current

• Oppose emf of a battery 

• All of these

1.       In a STEP UP transformer the voltage is

• Vs = Vp

• Vp> Vs

• Vs >Vp 

• None of these

Ampere hour is the unit of?

• quantity of charge

• power

• strength of current

•  energy

1.       An emf of 10 v is observed in one coil when the current is changing at the rate of 5 Ampere sec^-1 in the other coil. What is the mutual inductance of the coil?

• 50H      

• 40H

• 5H

• 2H

1.       For V=Vo sint find period

• zero

1.       Angle between coils of three phase supply is

• 120^o

•  240^o

• 360^o

• Both A and C

1.       Ratio of e.m.f. induced in secondary to rate of change of current in the primary is called:

• Mutual induction

• Mutual inductance

• Both A & B         

• Self inductance

1.       When the length is of 2 times and of (Number of turns remains same) current is of 9 times magnetic induction will be

• 2/9 B

• 9/2 B

• 18 B

• B/18

1.       S.I unit of magnetic induction is:

• Weber

• Tesla

• Gauss

• Weber m^-1