Along cylindrical capacitor is made of a central wire of radius a = 2.50 mm surrounded by a conducting shell of radius b = 7.50 mm. the gap between the plates is filled with a dielectric of constant k = 3.68 and a potential difference of av = 120 v is applied across the plates. what is the capacitance per unit length c for this device? a) c = 1.86 x 10-10 f/m b) c = 5.06 x 10-11 f/m c) c = 8.34 x 10-11 f/m d) c = 3.07 x 10-10 f/m

The capacitance per unit length is

(b) is correct option.

Explanation:

Given that,

Radius a= 2.50 mm

Radius b=7.50 mm

Dielectric constant = 3.68

Potential difference = 120 V

We need to calculate charge per length for the capacitance

Using formula of charge per length

Put the value into the formula

We know that,

We need to calculate the capacitance per unit length

Using formula of capacitance per unit length

Hence, The capacitance per unit length is

answer; i believe the correct answer is (40,000 j) good luck

b.a device that inputs heat into a cool object