Question

Determine the force exerted by two particles that have a charge of +0.35 Coulombs each and are 1 meter apart

Answer 1

The electric force between two charges is:

F = (9 x 10⁹) Q₁ Q₂ / D²

F is the force, in Newtons

Q₁ and Q₂ are the two charges, in Coulombs

D is the distance between them, in meters

For these two particles:

F = (9 x 10⁹) (0.35) (0.35) / (1)²

F = (9 x 0.35 x 0.35 x 10⁹) / (1)

F = 1.10 x 10⁹ Newtons

Thatsa lotta force . . . like 124 thousand tons !

The reason it's so big is because the charges in this question are so big ... 0.35 Coulombs each. 1 Coulomb is a huge amount of charge.

Each of the particles feels the same force, pushing it away from the other particle. (The electric force between two charges is always the same in both directions, just like the gravitational force between two masses.)

Answer 2

Acc. to columb's law;

• F = k × Q1Q2/r²

Clearly, from the question you have:

• Charge on both particles = +0.35 columbs
• Distance between them = 1 meter = 1 × 10-¹⁰ Å

Now just put them up in the formula:

F = k × Q1Q2/r²

F = 9 × 10⁹ × 0.35 × 0.35/1 × 10-¹⁰

F = 9 × 10⁹ × 35 × 35/ 10-¹⁰ × 100 × 100

F = 9 × 10⁹ × 35 × 35/ 10-¹⁰ × 10⁴

F = 9 × 10⁹ × 35 × 35/ 10-⁶

F = 9 × 10⁹+⁶ × 1225

F = 11025 × 10¹⁵