A tube of mercury with resistivity 9.84 × 10-7 Ω ∙ m has a uniform electric field of 23 N/C inside the mercury. How much current is flowing in the tube, if the radius of the tube is 0.495 mm? Question 16 options:

a. 280 A
b. 18 A
c. 180 A
d. 29 A"

Current, i = 18 A            

Explanation:

Given that,

Resistivity of mercury,

Electric field inside the mercury, E = 23 N/C

Radius of the tune, r =  0.495 mm

We need to find the current flowing in the tube. We know that the resistance in terms of length and area is given by :

Using Ohm's law, we get :

V = iR, i is current, R is resistance

So,

Since, (electric field)

or

i = 18 A

So, 18 A of current is flowing in the tube.