Electrostatic-II

A billion electrons are added to a body, its charge becomes

• 1.6 X 10^-19 C

• 1.6 X 10^-28 C

• -1.6 X 10^-10 C

• -1.6 X 10^-28 C

when 10¹⁴ electrons are removed from a neutral metal sphere, the charge on the sphere becomes:

• 16 X 10^-6 C

• -16X 10^-6 C

• 32 10^-6 C

• -32X 10^-6 C

A soap bubble is given a negative charge then its radius :

• decreases

• increases

• remains un-changed

• insufficient information.

In a circuit 20 C of charge is passed through a battery in a given time. The plates of the battery are maintained at PD of 20 V . Howmuch work is done by the battery?

• 400 J

• 300 J

• 200 J

• 100 J

Suppose the electrostatic potential at some points in space are given by V = ( x² - 2x ). The electrostatic field strength at X= 1 is :

• zero

• -2

• 2

• 4

A sure test of electrification is

• attraction

• repulsion

• friction

• induction

Two charges of 20μC and -50μC are placed 80 cm apart. The distance of the point from the smaller charge where the intensity will be zero is:

• 20 cm

• 35 cm

• 30 cm

• 25 cm

Flux coming out from a positive unit charge placed in air is :

• ε₀

• ε₀^-1

• 4πε₀

• (4πε₀ )^-1

The electric flux passing through the sphere, if an electric dipole is placed at the centre of a sphere is :

• 1/ε₀

• 2/ ε₀

• zero

• none of these

Two charges +q and -3q are placed at a distance of 1m apart. The points on the line joining two charges, where electric potential is zero, is :

• 0.25 m, 0.5 m

• 1 cm , 0.50 m

• 0.35 cm , 24 cm

• none of these