Two spherical objects are separated by a distance of 1.70 × 10-3 m. The objects are initially electrically neutral and are very small compared to the distance between them. Each object acquires the same negative charge due to the addition of electrons. As a result, each object experiences an electrostatic force that has a magnitude of 1.15 × 10-20 N. How many electrons

Consider the three point charges in the x-y plane as shown in the figure. y (cm) 90 80 70 60 50 40 30 20 10 0 Q1 Q2 0 10 20 30 40 50 60 70 80 90 x (cm) What is the total electrostatic energy of the system? The point charges have the following values: Q₁ = 5.01 nC, Q₂ = 6.47 nC, Q3 = -7.60 nC. Point charge Q3 is moved away to infinity by an external force. How much work did the external force perform in this process?

Red blood cells often become charged and can be treated as point charges. Healthy red blood cells are negatively charged, but unhealthy cells (due to the presence of a bacteria, for example) can become positively charged. In the figure, three red blood cells are oriented such that they are located on the corners of an equilateral triangle. The red blood cell charges are A = 1.90 pC, B = 6.50 pC, and C = -4.80 pC. Given these charges, what would the magnitude and direction of the electric field be at cell A? (1 pC = 1 x 10-12 c.) Magnitude- Direction-

Electrophoresis gel can separate charged DNA samples in an applied electric field. Suppose a DNA sample contains negative charges of 60 electrons. What is the magnitude of the electric force on this charge in a 2,000 N/C electric field? O 1.2 x 10^-14 N O 2.5 x 10^-14 N O 2.0 x 10^-15 N O 1.9 x 10^-14 N O 3.2 x 10^-16 N