-
In a circuit, L, C and R are connected in series with an alternating voltage source of frequency f. The current leads the voltage by 45°. The value of C is
-
-
1 πƒ(2πƒL - R) -
1 2 πƒ(2πƒL - R) -
1 πƒ(πƒL + R) -
1 πƒ(2πƒL + R)
-
Correct Option: D
From figure,
| tan 45º = | (1/ωC) - ωL | |
| R |
| ⇒ | 1 | - ωL = R |
| ωC |
| ⇒ | 1 | = R + ωL |
| ωC |
 | ∴ ω = | 2π | = 2μƒ |  | ||||
| T |
| C = | 1 | = | 1 |
| ω(R + ωL) | 2πƒ(R + 2πƒ L) |
