Question
Time constant of $$L-R$$ circuit will be
Time constant of $$L-R$$ circuit will be
A.
$$\frac{L}{R}$$
B.
$$\frac{2L}{R}$$
C.
$$\frac{L}{2R}$$
D.
None of these
Answer :
$$\frac{L}{2R}$$
Solution :
A circuit equivalent to the given circuit can be drawn as follows :
Where
$$\eqalign{ & {R_{{\text{eq}}}} = R + \frac{{2R \times 2R}}{{4R}} = R + R \cr & {R_{{\text{eq}}}} = 2R \cr} $$
∴ Time constant $$ = \frac{L}{{2R}}$$
A circuit equivalent to the given circuit can be drawn as follows :
Where
$$\eqalign{ & {R_{{\text{eq}}}} = R + \frac{{2R \times 2R}}{{4R}} = R + R \cr & {R_{{\text{eq}}}} = 2R \cr} $$
∴ Time constant $$ = \frac{L}{{2R}}$$
