Question

A coil of resistance 300 ohm and self inductance 1.5 henry is connected to an ac source of frequency The phase difference between voltage and current is

• A.
• B. $30 ^ { \circ }$
• C. $45 ^ { \circ }$
• D. $60 ^ { \circ }$

Answer 1

Answer: (C)

$45 ^ { \circ }$

Answer 2

By using $\tan \phi = \frac { X _ { L } } { R } = \frac { 2 \pi v L } { R }$ ⇒

$\tan \phi = \frac { 2 \pi \times \frac { 100 } { \pi } \times 1.5 } { 300 } = 1$ ⇒ φ = 45^o.