Physics Archive: Questions from 2024-04-12

Suppose a speck of dust in an electrostatic precipitator has 1.0000×10 12 protons in it and has a net charge of −5.00 nC (a very large charge for a small speck). How many electrons does it have? Negative charge of an electron = 1.602 × 10 −19 C 1.0312 × 10^12 e 2.0312 × 10^15 e 2.2312 × 10^12 e 2.0312 × 10^12 e

Two point particles with charges +3μC and +5μC are held in place by 3−N forces on each charge in appropriate directions. Find the distance between the charges. 0.185 m 0.55 m 0.21 m 0.45 m

Calculate the magnitude and direction of the electric field 2.0 m from a long wire that is charged uniformly at λ = 4.0 × 10−6 C/m. 6.6 × 10^4 N/C k 3.6 × 10^4 N/C k 4.6 × 10^4 N/C k 1.6 × 10^4 N/C k