Electric Circuits
The hot resistance of a tungsten lamp is about 10 times the cold resistance. Accordingly, cold resistance of a 100 W, 200 V lamp will be

 400 Ω.
 4 Ω.
  40 Ω.
 800 Ω.

ANSWER DOWNLOAD EXAMIANS APP

Electric Circuits
A battery of E Volts is supplying a steady current to a series circuit of total resistance RΩ and inductance L Henry. A part R1 of the total resistance is suddenly short circuited. Find the expression for current flowing through the battery subsequent to the operation.

 i = {E / R}[1-(R1 / R) *e - {(R - R1 )*t/L}
 i = {E / R1 - R)}(1- e - (R1 - R) t / L)
None of these
 i = {E / (R - R1)}[1-(R1 / R) *e- {(R - R1 )t/L}

ANSWER DOWNLOAD EXAMIANS APP