First slide

Coulumbs law

Question

Two identical charged spheres are suspended by strings of equal lengths. The strings make an angle of 30^o with each other. When suspended in a liquid of density 0.8 g cm^-3, the angle remains the same. If density of the material of the sphere is 1.6 g cm^-3, the dielectric constant of the liquid is :

Difficult

A

1
B

4
C

3
D

2

Solution

$\tan 30^{o} = \frac{V ρ_{s} g}{F_{e}}$
Inside liquid
$\tan 30^{o} = \frac{V (ρ_{s} - ρ_{l}) g}{F_{e} / k} or k (ρ_{s} - ρ_{l}) = ρ_{s} or k = (\frac{ρ_{s}}{ρ_{s} - ρ_{l}}) = 2$

Get Instant Solutions

When in doubt download our app. Now available Google Play Store- Doubts App

Recieve an sms with download link

Doubts App

OR

SCAN ME

Doubts App

Doubts App