Question

give the solution of this question

Answer 1

Formula used: V = Q/C = (Q₀/C) e^-t/RC
                        V = V₀ e^-t/RC                            
Kindly observe that e^-t/RC is a term and -t/RC is the power of e

According to the given data,
V = 1 v, V₀ = 50 v, t = 10

By substituting these values in formula,
                         1 v = (50 v) e^-10/RC
                          So, e^-10/RC = 1/50   →→→→ 1

The potential difference at t = 20 ms
                              = (50 v) e^-20/RC
                              = (50 v) (e^-10/RC)²
                              = (50 v) (1/50)²                           ( From 1)
                              = 1/50 v
                              = 0.02 v

Therefore, potential difference at t=20 ms is 0.02 v.