Question

A coil has an inductance of 2.5H and a resistance of 0.5 ohm. If the coil is suddenly

connected across a 6.0 volt battery, then the time required for the current to rise 0.63

of its final value is:​

Answer 1

Answer:

coil has an inductance of

and a resistance of

. If the coil is suddenly connected across a

volt battery, then the time required for the current to rise

Answer 2

Answer:

The time required is 5 seconds.

Explanation:

• The circuit whose data is given in the question is the LR circuit.
• The current through an LR circuit is calculated as,

                              $I=I_0(1-e^\frac{-Rt}{L})$        (1)

Where,

I=instantaneous current

I₀=maximum current flowing through the circuit

R=resistance of the coil

L=inductance of the coil

t=particular time at which we want to find the current

From the question we have,

I=0.63I₀

L=2.5H

R=0.5Ω

The potential of the battery(V)=6 volt

• The time it takes for the current in the L-R circuit to climb to 63% of its maximum value is called its time constant(τ). And it is calculated as,

                                            $\tau=\frac{L}{R}$      (2)

By putting the required variables in equation (2) we get;

                               $\tau=\frac{2.5}{0.5}$

                               $\tau=5 \ seconds$

Hence, the time required is 5 seconds.

#SPJ3