Question

A negative charge of –40nC exerts an attractive force of 12N on a second charge that is 0.050m away. What is the second charge?

Answer 1

Solution:-

Given –

Charge (q1) = -40 nC, its converted into coulomb (q1) = -40 *10^-9 C

Force (F) = 12 N

Distance (r) = 0.050 m

Using electric force equation,

Formula-               F = k*q1q2 / r²

Where,

F = force                                                                                     

q1 = first charge

q2 = second charge

r = distance between two charges

K – Coulomb constant and its value is 9*10⁹ c

Calculate q2,

q2 = F*(r²) / k*q1

Putting given value in above equation, and calculate q2

q2 = 12*(0.050)² / 9*10⁹ (-40*10^-9)

q2 = 0.03 / -360

q2 = -8.33*10^-5 C

The second charge is q2 = -8.33*10^-5 C