Two coils having equal resistance but different inductances

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Two coils having equal resistance but different inductances are connected in series. the time constant of the series combination is the

1. sum of the time constants of the individual coils
2. average of the time constants of individual coils
3. geometric mean of the time constants of the individual coils
4. product of the time constants of the individual coils

Correct Option: B

T =	L₁ + L₂	=	L₁ + L₂	=	1		L₁	+	L₂
	R₁ + R₂		2R₂		2		R		R

Thus time constant is the average of the time constant of individual coils.