Question

The inductive reactance of a coil is 1500 n. If its inductance and the frequency of A.C. supply are both doubled, then the reactance will become ______.

Options

• 6000 `Omega`

• 4000 `Omega`

• 8000 `Omega`

• 16000 `Omega`

Answer 1

The inductive reactance of a coil is 1500 n. If its inductance and the frequency of A.C. supply are both doubled, then the reactance will become 6000 `Omega`

Explanation:

` "X"_"L" = "fL" => "X"_("L"_2)/"X"_("L"_1) = ("f"_2"L"_2)/("f"_1"L"_1) = (2"f"_1 xx 2"L"_1)/("f"_1"L"_1)`= 4

∴ `"X"_("L"_2)` = 4 x 1500 = 6000 `Omega`