Question

An electrostatic paint sprayer has a 0.8 m diameter metal sphere at a potential of 39 kV that repels paint droplets onto a grounded object. What charge is on the sphere? Give answer in terms of 10^-7 C.

Answer 1

The charge on the sphere is
`1.735* 10^(- 7) C`

Solution:

The electric potential on the surface of a sphere of radius 'b' and charge 'Q' is given by:

`V_(sphere) = (Q)/(4\pi\epsilon_(o)b)`

According to the question:

Diameter, b = 0.8 m

Potential of sphere,
`V_(sphere) = 39 kV = 39000 V`

`{4\pi\epsilon_(o)(0.8)/(2)* 39000 = Q`

Q =
`1.735* 10^(- 7) C`