A charged object is launched inside a time varying electric field. Its motion is recorded by a video camera on a video tape. When it is at a certain moment $A$ , its position vector $\vec r$, velocity $\vec v$ and acceleration $\vec a$ are measured. A student watches the video at a later time but mistakenly plays the tape in the reverse direction. What is the position, velocity, and acceleration of the object, at moment $A$ observed by the student respectively?
$\vec r,\vec v,\vec a$
$- \vec r, -\vec v, -\vec a$
$\vec r,- \vec v,\vec a$
$\vec r,\vec v,- \vec a$
A spherical shell with an inner radius $'a'$ and an outer radius $'b'$ is made of conducting material. A point charge $+Q$ is placed at the centre of the spherical shell and a total charge $-q$ is placed on the shell. Final charge distribution on the surfaces as
A capacitor is charged by using a battery which is then disconnected. A dielectric slab is then slipped between the plates, which results in
If the electric flux entering and leaving an enclosed surface respectively is ${\phi _1}$ and ${\phi _2}$ the electric charge inside the surface will be
For shown situation of two dipoles the nature of forces between them are
If potential at centre of uniformaly charged ring is $V_0$ then electric field at its centre will be (assume radius $=R$)