For the value of obtained in the above question, the time taken for 95% of the stored energy to be dissipated is close to
(a) 0.10 s (b) 0.15 s
(c) 0.50 s (d) 1.0 s
E1 is the stored energy and E2 is the dissipated energy. So,
i12i22=E1E2=0.95
Therefore, i22=0.95i12⇒i2=0.9746i1
When the switch is in position 2,
i(t)=i1e−(R/L)t=2e−(60/10)t=2e−6t (i)
After 95% of energy dissipation,
i(t) = 2 – 2 × 0.97 = 0.05 A (ii)
Substituting Eq. (ii) in Eq. (i), we get
0.05=2e−6t⇒t=0.5 s