Four point positive charges are held at the vertices of a square in a horizontal plane. Their masses are 1 kg, 2kg,3kg and 4kg. Another point positive charge of mass
10 kg is kept on the axis of the square. The weight of this fifth charge is balanced by the electrostatic force due to those four charges. If the four charges on the vertices are
released such that they can freely move in any direction (vertical, horizontal etc.) then the acceleration of the centre of mass of the four charges immediately after the release is (use $g = 10 m / s^{2}$ )

Moderate

Solution

The net electrostatic force on 10 kg charge should be F_e= 100 N upwards
$∴$ Net electrostatic force on remaining four charges: 100 N downwards
$∴$ Net force on remaining four charges : Net electrostatic force + net weight = 100 N + 100 N = 200N downwards
$∴$ Acceleration of centre of mass of the four charges immediately after the release
$= \frac{Net Force}{Net mass} = \frac{200}{10} = 20 m / s^{2} downwards$

Get Instant Solutions

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

Recieve an sms with download link

SCAN ME