Consider 4 charges that all sit on the x-axis as illustrated in the figure below

Question

Consider 4 charges that all sit on the x-axis as illustrated in the figure below. In the following questions, pay close attention to what the question is actually asking for and assume that q = 2.5 nC

a) the magnitude and direction of the force exerted on the -2q charge by the +q charge.

b) Determine the net force exerted on the +3q charge by the other three charges.

c) Determine the electric field due to the -2q charge at the point x = 0 cm.

d) Determine the net electric field due to all charges at the point x = 10 cm.

Explanation / Answer

as the electric force between the charges is given as

F = k * q1 * q2/d^2

a) force on -2q due to + q

F = 9*10^9 * 2.5 *10^-9 * 2 * 2.5 *10^-9/(13)^2 i

F = 6.657 *10^-10 i N

the force on the charge -2q is 6.657 *10^-10 N in positive x - dorection

b)

net force on the charge 3q

F = 9*10^9 * 3 * 2.5 *10^-9 * 2.5 *10^-9 *(1/3^2 + 1/6^2 - 1/7^2) i

F = 2 *10^-8 N i

the force on the charge 3q is 2 *10^-8 N in positive x - direction

c)

electric field due to -2q

E = 9*10^9 * 2 * 2.5 *10^-9/1^2

E = 45 N/C

the electric field is 45 N/C

d)

at x = 10 m

electric field = 9*10^9 * 2.5 *10^-9 *(-2/9^2 + 1/5^2 + 3/2^2 + 1/4^2)

electric field = 18.62 N

the electric field at x = 10 m is 18.62 N

Related Questions

Navigate

• Browse (All)
• Browse C
• Subjects

Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.