A coil of 200 Ω resistance and 1 H inductance is connected to an a.c. source of frequency (100/π)Hz, phase angle between potential and current will be:

Question

A coil of 200 Ω resistance and 1 H inductance is connected to an a.c. source of frequency (100/π)Hz, phase angle between potential and current will be: (A) 30° (B) 45° (C) 60° (D) 90°

Tardigrade Admin · Accepted Answer

cos φ =(R/Z)=(R/√(R)2+ω2 L2) =(200/√2002+(200)2 ×(1)2) cos φ=(1/√2) =φ=45°

Q. A coil of $200Ω$ resistance and $1 H$ inductance is connected to an a.c. source of frequency $\frac{100}{π} Hz$ , phase angle between potential and current will be:

$3 0^{\circ}$

$4 5^{\circ}$

$6 0^{\circ}$

$9 0^{\circ}$

$cos ϕ = \frac{R}{Z} = \frac{R}{( R ) ^{2} + ω ^{2} L ^{2}}$
$= \frac{200}{20 0 ^{2} + ( 200 ) ^{2} \times ( 1 ) ^{2}}$
$cos ϕ = \frac{1}{2} = ϕ = 4 5^{\circ}$

Q. A coil of 200Ω resistance and 1H inductance is connected to an a.c. source of frequency π100​Hz, phase angle between potential and current will be:

30∘

45∘

60∘

90∘