List of practice Questions

By which of the following methods, new and better varieties of plants can be formed?
A charged dust particle of radius $ 5\times {{10}^{-7}}m $ is located in a horizontal electric field having an intensity of $ 6.28\times {{10}^{5}}V{{m}^{-1}} $ . The surrounding medium is air with coefficient of viscosity $ \eta =1.6\times {{10}^{-5}}N-s{{m}^{-2}} $ . If this particle moves with a uniform horizontal speed $ 0.02\,m{{s}^{-1}} $ . Find the number of electrons on it.
Ultraviolet light wavelength $300 \,nm$ and intensity $1.0 \,Wm ^{-2}$ falls on the surface of a photoelectric material. If one percent of the incident photons produce photoelectrons, then the number of photoelectrons emitted per second from an area of $1.0 \,cm ^{2}$ of the surface is nearly
Adenosine is an example of
Buna-$N$ synthetic rubber is a copolymer of
During inspiration, the diaphragm
The substance with the highest calorific value is
The spin only magnetic moment value (in $ $B.M.$ $ unit) of $ Cr(CO)_{6} $ is
The species inhabiting the same geographical areas are
The shortest distance between the line $y-x=1$ and the curve $x = y^2$ is
The shade tolerant plants are known as
The shape of $ Xe{{F}_{4}} $ molecule and hybridisation of xenon in it are
The set representing the correct order of ionic radius is :
The radius of an electron orbit in a hydrogen atom is of the order of
The longest bone of the human body is
The homologue of ethyne is
The height of a geostationary satellite is
The heat of atomisation of $PH_3(g)$ and $ P_2H_4(g)$ are $ 954 kJ\, mol^{-1}$ and $1485\, kJ\, mol^{-1}$ respectively .The P-P bond energy in $kJ\, mol^{-1}$ is
The enzyme which converts starch into maltose is
The ellipse $x^2 + 4y^2 = 4$ is inscribed in a rectangle aligned with the coordinate axes, which in turn in inscribed in another ellipse that passes through the point $(4, 0)$. Then the equation of the ellipse is
$ 2n=16 $ in a primary spermatocyte, which is in metaphase of first meiotic division: What shall be the total number of chromatids in each of the secondary spermatocyte?
Streptomycin is obtained from
Some iron beads are embedded in wax ball which is just floating in water. The volume of ball is $18 \,cm^{3}$ and relative density of wax is $0.9$. Then mass of the iron trapped in the ball is
Satiety centres of brain is present on
Rh factor is present in