Test JEE Level 01

How will you charge a metallic sphere by using the method of induction. The sphere should acquire negative charge.

There are four charged particles in a system. Two charged particles each of 10 μC are placed at the vertices of equilateral triangle of side 10 cm. One charged particle carrying 20 μC , is placed at the third vertex of the triangle. If fourth particle of charge -30 μC is placed at the centroid of the triangle, find the net force acting on the fourth charged particle.

Three charged particles are lying on the vertices of an equilateral triangle of side 20 cm. If two particles carry 20 μC each while third particle carry -10μC, find the net force acting on the negatively charged particle.