An electron and a proton have charges of an equal magnitude but opposite sign of 1.6 . 1019 C. If the electron and proton in a hydrogen atom are separated by a distance of 5 . 1011 m, what are the magnitude and direction of the electrostatic force exerted on the electron by the proton?

The electric field near the surface of the earthpoints downward and has a magnitude of60 N/C.Compare the upward electric force on anelectron with the downward gravitationalforce; i.e., what is the ratio FeFg? The elementary charge is 1.6 × 10−19 C and the massof an electron is 9.11 × 10−31 kg.   What is the magnitude of the charge thatshould be placed on a coin of mass 4.4 g sothat the electric force balances the weight ofthe coin near the earth’s surface?Answer in units of C.

Two positive charges, one 4.0 ?Cand the other 8.0 ?C, are separated by a distance of 15 cm. What is the magnitude of the electrostatic force that each charge exerts upon the other?1.44 N0.0192 N 0.0144 N1.92 N

Point charges q1=q2=6.91⨯10-9C are fixed on the y-axis at y = 85.9m and y = -85.9m. There is a charge q3 with 3.90⨯10-9 C at x=8.35m, y= -0.365 .  The point P is at x=8.35m, y=0. What is the vertical (y) component of the total electric field at P, due to all three charges in Newtons/Coulomb? (Use the convention that positive values indicate an upwards electric field and negative values indicate a downward force.) Calculate to 1 decimal place. You must draw and label a diagram.