Electric Charge...

A cylinder of radius $$R$$ and length $$l$$ is placed in a uniform electric field $$E$$ parallel to the axis of the cylinder. The total flux over the curved surface of the cylinder is :

Identify the wrong statement in the following. Coulomb's law correctly describes the electric force that

Identify the correct statement about the charges $$q_1$$ and $$q_2$$ :

Two small objects each with a net charge of +Q exert a force of magnitude F on each other. We replace one of the objects with another whose net charge is + 4Q. We move the +Q and +4Q charges to be 3 times as far apart as they were. What is the magnitude of the force on the +4Q charge ?

A thin insulator rod is placed between two unlike point charges $$ +q_1 $$ and $$ q_2 $$ . For this situation tick the correct alternative (s)

A particle A having a charge of $$2.0 \times 10^{-6}$$C and a mass of 100 g is fixed at the bottom of a smooth inclined plane of inclination $$30^{\circ}$$. Where should another particle B having same charge and mass, be placed on the inclined plane so that B may remain in equilibrium?(Take g= $$10 m/s^2$$)

The electric field in a region of space is given by $$\vec{E} = 5\widehat{i} + 2\widehat{j} \ N/C$$. The flux of $$\vec{E}$$ due to this field through an area $$1m^2$$ lying in the y-z plane, in SI units, is :

In the diagram shown, the charge $$+Q$$ is fixed. Another charge $$+2q$$ and mass $$M$$ is projected from a distance $$R$$ from the fixed charge. Minimum separation between the two charges if the velocity becomes $$\displaystyle \frac{1}{\sqrt 3}$$ times of the projected velocity, at this moment is (Assume gravity to be absent):

Two charged particles are placed at a distance $$1.0 cm$$ apart. What is the minimum possible magnitude of the electric force acting on each charge?

Each of the two point charges are doubled and their distance is halved. Force of interaction becomes n times, where n is