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A Charge of 1.0 C is Placed at the Top of Your College Building and Another Equal Charge at the Top of Your House. Take the Separation Between the Two Charges to Be 2.0 Km. - Physics

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प्रश्न

A charge of 1.0 C is placed at the top of your college building and another equal charge at the top of your house. Take the separation between the two charges to be 2.0 km. Find the force exerted by the charges on each other. How many times your weight is this force?

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उत्तर

Given:
q1 = q2 = q = 1.0 C
Distance between the charges, r = 2 km = 2 × 103 m
By Coulomb's Law, electrostatic force, 

\[F = \frac{1}{4\pi \epsilon_0}\frac{q_1 q_2}{r^2}\]
\[F = 9 \times {10}^9 \times \frac{1 \times 1}{\left( 2 \times {10}^3 \right)^2}\]
\[ = 2 . 25 \times {10}^3 N\] 

Let my mass, m, be 50 kg.
Weight of my body, W = mg
⇒ W = 50 × 10 N = 500 N
Now,
\[\frac{\text { Weight of my body }}{\text{ Force between the charges }} = \frac{500}{2 . 25 \times {10}^3} = \frac{1}{4 . 5}\]

So, the force between the charges is 4.5 times the weight of my body.

 

 

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पाठ 7: Electric Field and Potential - Exercises [पृष्ठ १२१]

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एचसी वर्मा Concepts of Physics Vol. 2 [English] Class 11 and 12
पाठ 7 Electric Field and Potential
Exercises | Q 2 | पृष्ठ १२१

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