# Consider a coin of Example 1.20. It is electrically neutral and contains equal amounts of positive and negative charge of magnitude 34.8 kC. Suppose that these equal charges were concentrated in two point charges separated by (i) 1 cm , (ii) 100 m ( ∼length of a long building), and (iii) 106 m (radius of the earth). Find the force on each such point charge in each of the three cases. What do you conclude from these results?

Let, q be the magnitude of the charge.

Also let,

r1 be the distance in first case.

r2 be the distance in second case.

r3 be the distance in third case.

According to the question,

q = ± 34.8 KC and i.e. = ± 3.48 × 104 C

r1 = 1 cm = 10‒2 m

r2 = 100 m

r3 = 106 m

Let’s assume, F1, F2 and F3 are forces in first, second and third case respectively, then by using

×

So we have,

It is not easy to disturb the electrical neutrality.

When the charges are separated as point charges the charges exert a huge force.

Rate this question :

How useful is this solution?
We strive to provide quality solutions. Please rate us to serve you better.
Related Videos
Electric Charges and Fields - 0556 mins
Electric Charges and Fields - 0854 mins
Electric Charges and Fields - 0256 mins
Electric Charges and Fields - 1055 mins
Electric Charges and Fields - 0352 mins
Electric Charges and Fields - 0155 mins
Electric Charges and Fields - 0946 mins
Electric Charges and Fields - 0447 mins
Electric Charges and Fields - 0658 mins
Electric Charges and Fields - 0751 mins
Try our Mini CourseMaster Important Topics in 7 DaysLearn from IITians, NITians, Doctors & Academic Experts
Dedicated counsellor for each student
24X7 Doubt Resolution
Daily Report Card
Detailed Performance Evaluation
view all courses