Part A By what distance do two objects carrying 1.0 C of charge each have to be separated before the electric force exerted on each object is 4.0 N? Express your answer with the appropriate units.

Part B How much charge should be placed on each of two small objects separated by 1.0 m so that the electric force exerted on each is 4.0 N? Express your answer with the appropriate units.

Part A: 4.74*10⁴ m

Part B: 0.000211 C

Explanation:

Part A:

From coulombs law,

F = kq²/r² ... Equation 1

Note: The two object are carrying equal charges.

Where F = Electric force, q = charge, r = distance of separation, k = proportionality constant

Given: F = 4.0 N, q = 1.0 C,

Constant: k = 1/4πe₀ = 9*10⁹ Nm²/C²

Substituting these values into equation 1,

4 = 9*10⁹ (1²) / r²

r² = (9*10⁹) / 4

r² = 2.25*10⁹

r = √ (2.25*10⁹)

r = 4.74*10⁴ m.

Part 2:

F = kq²/r²

Making q the subject of the equation

q = √ (Fr²/k) ... Equation 2

Where: F = 4.0 N, r = 1.0 m, k = 9*10⁹ Nm²/c²

Substituting these values into equation 2

q = √ (4*1² / (9*10⁹)

q = 2.11/10⁴

q = 0.000211 C.