DPP3 Electric charge and field

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

• Decreases

• Increases

• Remains unchanged

• Nothing can be predicted as information is insufficient

There are two metallic spheres of same radii but one is solid and the other is hollow, then

• Solid sphere can be given more charge

• Hollow sphere can be given more charge

• They can be charged equally (maximum)

• None of the above

One metallic sphere A is given positive charge whereas another identical metallic sphere B of exactly same mass as of A is given equal amount of negative charge. Then

• Mass of A and mass of B still remain equal

• Mass of A increases

• Mass of B decreases

• Mass of B increases

Two similar spheres having +q and -q charge are kept at a certain distance. F force acts between the two. If in the middle of two spheres, another similar sphere having +q charge is kept, then it experience a force in magnitude and direction as

• Zero having no direction

• 8F towards +q charge

• 8F towards -q charge

• 4F towards +q charge

Three charges are placed at the vertices of an equilateral triangle of side ‘a’ as shown in the following figure. The force experienced by the charge placed at the vertex A in a direction normal to BC is

• $\frac{Q^2}{\left(4\pi\epsilon_oa^2\right)}$

• $-\frac{Q^2}{\left(4\pi\epsilon_oa^2\right)}$

• zero

• $\frac{Q^2}{\left(2\pi\epsilon_oa^2\right)}$

In the electric field of a point charge q , a certain charge is carried from point A to ,B , C,D and E . Then the work done

• Is least along the path AB

• Is least along the path AD

• Is zero along all the pathsAB,AC,AD and AE

• Is least along AE