Question

a charge +6 C experiences a force of 2mN in +x direction.
a)what was the electric field there before charge was placed ?
b)describe the force which a -2c charge would experience if it is located at the point in place of the +6c

for a) i assumed the charge is 0 'cos there's no charge placed before that.is it correct?

Answer 1

2m N/ 6 C = E in Newtons/coulomb

(-2/6) (2m N)
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for a) i assumed the charge is 0 'cos there's no charge placed before that.is it correct?

NO! E is force experienced by test charge of one coulomb