Question

A parallel plate capacitor with air between the plates is charged to a potential difference of 500V and then insulated. A plastic plate is inserted between the plates filling the whole gap. The potential difference between the plates now becomes 75V. The dielectric constant of plastic is(a) 10/3(b) 5(c) 20/3(d) 10

Answer 1

10/3 is your answer mate

Answer 2

Answer:

C) 20/3

Explanation:

Potential difference = 500V (Given)

Potential difference after inserting plate = 75V (Given)

The electric field is related to the potential as V= Ed.

Thus,

v0 = q/c0

V = q/c = v/V0 = c/C0

= c/C0 = 500/75

= 20/3

Since, we already know that C = kC0

                                                   = k = 20/3

Thus, the dielectric constant of plastic is 20/3