The time constants for a series RC circuit with a capacitanc

The time constants for a series RC circuit with a capacitance of 4.70 µF and a series RL circuit with an inductance of 3.50 H are identical.

(a) What is the resistance R in the two circuits?

(b) What is the common time constant for the two circuits?
s

The time constants for a series RC circuit with a capacitance of 4.70 µF and a series RL circuit with an inductance of 3.50 H are identical.

(a) What is the resistance R in the two circuits?

(b) What is the common time constant for the two circuits?
s

a) time constant for RC circuit = RC

time constant for TL circuit =L/R

equating both we get R = (L/C)^1/2 = (3.50/4.70 *10^-6)^1/2 =862.95 ohm

b) time constant = RC= 862.95 * 4.70 * 10^-6 =4.055 * 10^-3 s