Select the correct alternative
The charge gained by the uncharged body from a charged body due to conduction is equal to half of the total charge initially present
The magnitude of charge increases with the increase in velocity of charge
Charge can exist without matter although matter can not exist without charge
Between two non-magnetic substances repulsion is the true test of electrification (electrification means body has net charge)
Explain the superposition principle for static electric forces and write its general equation.
A conducting sphere of radius $R$, and carrying a charge $q$ is joined to a conducting sphere of radius $2R$, and carrying a charge $-2q$. The charge flowing between them will be
A charge $Q$ is placed at each of the opposite corners of a square. A charge $q$ is placed at each of the other two corners. If the net electrical force on $Q$ is zero, then $\frac{Q}{q}=$ ______
Positive point charges are placed at the vertices of a star shape as shown in the figure. Direction of the electrostatic force on a negative point charge at the centre $O$ of the star is
Two charged spheres separated at a distance $d$ exert a force $F$ on each other. If they are immersed in a liquid of dielectric constant $2$, then what is the force (if all conditions are same)