Question

Two point charges 1C each separated by 1Km . Find the electrostatic force of

repulsion between them​

Answer 1

Answer:

• The electrostatic Repulsion (F) between the charges is 9 × 10³ N.

Given:

1. Two charges have a magnitude of 1 C.
2. Distance of separation (r) = 1 Km.

Explanation:

$\rule{300}{1.5}$

From coulomb's law we know,

⇒ F = (1 / 4 π ε₀) × (q₁ q₂ / r²)

Where,

• F Denotes Electrostatic force of repulsion.
• ε₀ Denotes Permmittivity of free space.
• q₁ Denotes Charge.
• q₂  Denotes Charge.
• r Denotes Distance.

Now,

⇒ F = (1 / 4 π ε₀) × (q₁ q₂ / r²)

Substituting the values,

∵ [ q₁ = q₂ = q = 1 ]

⇒ F = (1 / 4 π ε₀) × (1 C × 1 C) / (1 km)²

⇒ F = (1 / 4 π ε₀) × (1 C × 1 C) / (10³ m)²

∵ [ 1 Km = 10³ m ] (S.I units)

⇒ F = (1 / 4 π ε₀) × 1 / 10⁶

We Know,

1 / 4 π ε₀ has an equivalent value of 9 × 10⁹

Substituting,

⇒ F = 9 × 10⁹ × 1 / 10⁶

⇒ F = 9 × 10⁹ × 1 × 10⁻⁶

⇒ F = 9 × 10⁹⁻⁶

⇒ F = 9 × 10³

⇒ F = 9 × 10³ N

∴ The electrostatic Repulsion (F) between the charges is 9 × 10³ N.

$\rule{300}{1.5}$

Answer 2

$\large{\underline{\underline{\mathfrak{Answer :}}}}$

• Electrostatic force between points is 9 × 10³ N

$\rule{200}{0.5}$

$\underline{\underline{\mathfrak{Step-By-Step-Explanation :}}}$

Given :

• First Charge (Q1) = 1 C
• Second Charge (Q2) = 1 C
• Distance between charges (d) = 1 km = 10³ m

$\rule{200}{1}$

To Find :

• Electrostatic Force between the charges

________________________

Solution :

Use Coulomb's Law

$\large{\boxed{\sf{F \: = \: k \dfrac{Q_1 Q_2}{d^2}}}} \\ \\ \implies {\sf{F \: = \: k \dfrac{1 \: \times \: 1}{(10^3)^2}}} \\ \\ \implies {\sf{F \: = \: \dfrac{k}{10^6}}} \\ \\ \footnotesize{\underline{\sf{\dag \: \: \: \: \: \: \: \: Value \: of \: k \: is \: 9 \: \times \: 10^9 \: \: \: \: \: \: \: \: }}} \\ \\ \implies {\sf{F \: = \: \dfrac{9 \: \times \: 10^9}{10^6}}} \\ \\ \implies {\sf{F \: = \: 9 \: \times \: 10^{9 \: - \: 6}}} \\ \\ \implies {\sf{F \: = \: 9 \: \times \: 10^3}} \\ \\ \underline{\sf{\therefore \: Electrostatic \: force \: between \: charges \: is \: 9 \: \times \: 10^3 \: N}}$