NEET 2021 Question Paper Mock Test

Two charged spherical conductors of radius $R_1$ and $R_2$ are connected by a wire. Then the ratio of surface charge densities of the sphere $({\sigma }_1/{\sigma }_2)$ is:

A convex lens ‘A’ of focal length $20\text{cm}$ and a concave lens ‘B’ of focal length $5\text{cm}$ are kept along the same axis with a distance ‘$d$ ’ between them. If a parallel beam of light falling on ‘A’ leaves ‘B’ as a parallel beam, then the distance ‘$d$ ’ in cm will be:

An infinitely long straight conductor carries a current of $5\text{A}$. An electron is moving with a speed of $10^5\text{m/s}$ parallel to the conductor. The perpendicular distance between the electron and the conductor is $20\text{cm}$ at an instant. Calculate the magnitude of the force experienced by the electron at the instant.

If $E$ and $G$ respectively denote energy and gravitational constant, then $E/G$ has dimensions of:

The velocity of a small ball of mass $M$ and density $d$, when dropped in a container filled with glycerine becomes constant after some time. If the density of glycerine is $d/2$, then the viscous force acting on the ball will be: