Question

An electric lamp which runs at 80 volt d.c. and consumes 10 ampere is connected to 100 volt, 50 Hz a.c. mains. Calculate the inductance of the choke required.

Answer 1

Answer:

L= 1.9 * 10^-2 H

Explanation:

Here, V= 80V, I= 10A,

R=  V I

=  80 *10

 = 8Ω

E(subscript v)= 100V ,v= 50Hz, I(subscript v)= I= 10A ,L=?

If Z is impedance of lamp and choke coil,

then Z=  E(subscript v) *I(subscript v)

=  100 *10

 =100Ω

As R^2+X (subscript L)^2 =Z^2

∴X (subscript L )^2

=Z^2 - R^2 =100-64=36, X(subscript )L=6Ω

Now X(subscript L)=ωL=2πvL

∴L= X(subscript L) /2πv

 = 6*7/ 2*22*50

 =1.9*10^-2 H

Answer 2

Best solution for this numerical.