You need to construct a 100 pF capacitor for a science project. You plan to cut two L x L metal squares and insert small spacers between their corners. The thinnest spacers you have are 0.20 mm thick. What is the proper value of L?

value of L = 4.75 cm

Explanation:

given data

capacitor =  100 pF = 100 × F

thick = 0.20 mm = 2 ×  m

solution

we get here area of each plate that is

area = L²   .......................1

and

Capacitance, C = εo A ÷ d    ..................2

put here value so we get

100 × = 8.854 ×   × L² ÷  ( 2 × )

solve it and we will get

L =  0.047528 m

value of L = 4.75 cm