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Can you charged particles at 1 m apart exert and 1 N force on each other. If the magnitude of each charges is doubled the force on each particle will be 1 N2 N4 N8 N

User Eduard Grigorescu
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1 Answer

9 votes
9 votes

Given:

Distance between particles = 1 m

Force exerted = 1 N

Let's find the force on each particle if he magnitude of each charge is doubled.

Apply the Columb's Law:


F=(kQ_1Q_2)/(r^2)

Where:

F is the force

Q1 is the charge of particle 1

Q2 is the charge of particle 2

r is the distance between the particles.

Rewrite the equation for Q1Q2


\begin{gathered} Q_1Q_2=(Fr^2)/(k) \\ \\ \\ Q_1Q_2=(1r^2)/(k) \end{gathered}

If the magnitude is doubled, we have:

Q1 = 1 x 2 = 2Q1

Q2 = 1 x 2 = 2Q2

Hence, we have:


F=\frac{k2Q_12Q_2_{}}{r^2}

Rewrite the equation for Q1Q2:


Q_1Q_2=(Fr^2)/(4k)

We have the equations for Q1Q2:


\begin{gathered} Q_1Q_2=(r^2)/(k) \\ \\ Q_1Q_2=(Fr^2)/(4k) \end{gathered}

Eliminate the equal sides of both eqautions and equate:


(Fr^2)/(4k)=(r^2)/(k)

Make F subject of the equation:

Cross multiply


\begin{gathered} Fr^2k=4r^2k \\ \\ \text{Divide both sides by r}^2k\colon \\ (Fr^2k)/(r^2k)=(4r^2k)/(r^2k) \\ \\ F=4\text{ N} \end{gathered}

Therefore, when the magnitude of each charge is doubled, the force on each particle will be 4 N

ANSWER:

4 N

User Jason James
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