Chapter 22, Problem 41P

SSM A charged cloud system produces an electric field in the air near Earth’s surface. A particle of charge -2.0 × 10^-9 C is acted on by a downward electrostatic force of 3.0 × 10^-6 N when placed in this field. (a) What is the magnitude of the electric field? What are the (b) magnitude and (c) direction of the electrostatic force ${\stackrel{\to }{F}}_{el}$ on the proton placed in this Geld? (d) What is the magnitude of the gravitational force ${\stackrel{\to }{F}}_g$ on the proton? (e) What is the ratio F_el/F_g in this case?