List of practice Questions

To what temperature must a neon gas sample be if the initial volume of gas at 75$^\circ$C is decreased by 15.0% by coolingthe gas

To which class of dyes does Malachite green belong ?

Tobacco consumption is known to stimulate secretion of adrenaline and nor-adrenaline. The component causing this could be

To shield an instrument from an external magnetic field it may be placed in a cabinet made of :

To shield an instrument from external magnetic field, it is placed inside a cabin made from

To what depth must a rubber ball be taken in deep sea so that its volume is decreased by $0.1 \%$. (Take, density of sea water =$10^{3} \, kg$ $m^{-3}$, bulk modulus of rubber =$9\times10^{8}N$ $m^{-2}$, $g=10 \,m$ $s^{-2})$

To open a lock, a key is taken out of a collection of n keys at random. If the lock is not opened with this key, it is put back into the collection and another key is tried. The process is repeated again and again. It is given that with only one key in the collection, the lock can be opened, the probability that the lock will open in n trials is

To initiate cell plasmolysis, the salt solution should be

To maintain a rotor at a uniform angular speed of $200\,rad\,s^{-1}$ an engine needs to transmit a torque of $180\,Nm$. The power of the engine required is (Assume the efficiency of the engine as 100%).

To maximize the objective function $z = 2x + 3y $ under the constraints $x + y \leq 30, x - y \geq 0 , y \leq 12, x \leq 20 , y \geq 3$ and $x ,y \geq 0 $

To increase sugar production in sugarcanes, they are sprayed with

To find the distance $d$ over which a signal can be seen clearly in foggy conditions, a railways engineer uses dimensional analysis and assumes that the distance depends on the mass density $\rho$ of the fog, intensity (power/area) $S$ of the light from the signal and its frequency $v$. The engineer finds that $d$ is proportional to $S^{1/n}$. The value of $n$ is

To get three images of a single object, one should have two plane mirrors at an angle of

To correct myopia, the focal length of the concave lens should be:

To derive the tangent formula, the following steps are given: 1. $\tan\left(A + B\right) = \frac{\frac{\sin A \cos B}{\cos A \cos B} + \frac{\cos A \sin B}{\cos A \cos B}}{\frac{\cos A \cos B}{\sin A \sin B} + \frac{\sin A \sin B}{\cos A \cos B}}$ 2. $\tan\left(A + B\right) = \frac{\sin\left(A + B\right)}{\cos\left(A + B\right)} $ 3. $\tan\left(A + B\right) = \frac{\sin A \cos B + \cos A \sin B}{\cos A \cos B - \sin A \sin B}$ 4.$ \tan\left(A + B\right) = \frac{\tan A + \tan B}{1- \tan A \tan B} $ Their correct and proper sequential form to derive the formula is:

To differentiate between pentan-$2$-one and pentan-$3$-one a test is carried out. Which of the following is the correct answer?

Time period of SHM is given by T = 2$\pi$ [displacement / acceleration]$^{1/2}$. When displacement increases, the time period

Time taken for an electron to complete one revolution in the Bohr orbit of hydrogen atom is

Tin and lead can be refined by

Tip of ecological pyramid is occupied by

Time period of oscillation of a spring is $12\, s$ on earth. What shall be the time period if it is taken to moon?

Threshold wavelength depends upon:

Thyroxine is chemically

Tickets are numbered from 1 to 100. They are well shuffled and a ticket is drawn at random. Probability that the drawn ticket has a number 5 or multiple of 5 is

Three vessels $A$, $B$ and $C$ of different shapes contain a water upto the same height as shown in the figure. $P_{A}$, $P_{B}$ and $P_{c}$ be the pressures exerted by the water at the bottom of the vessels $A$, $B$ and $C$ respectively Then