List of practice Questions

A jar full of whisky contains 40% alcohol. A part of this whisky is replaced by another containing 19% alcohol and now the percentage of alcohol becomes 26%. The quantity of whisky replaced is:

After two hours, one-sixteenth of the starting amount of a certain radioactive isotope remained undecayed. The half life of the isotope is

A capillary tube of radius $R$ is immersed in water and water rises in it to a height $H$. Mass of water in the capillary tube is $M$. If the radius of the tube is doubled, mass of water that will rise in the capillary tube will now be :

A charged particle moves through a magnetic field perpendicular to its direction, then

Two conducting shells of radius $a$ and $b$ are connected by conducting wire as shown in figure. The capacity of system is :

A dioecious flowering plant prevents both:

Match the following sexually transmitted diseases (Column - I) with their causative agent (Column - II) and select the correct option.

Column - I		Column- II
(a)	Gonorrhea	(i)	HIV
(b)	Syphilis	(ii)	Neisseria
(c)	Genital Warts	(iii)	Treponema
(d)	AIDS	(iv)	Human Papilloma virus

Which of the following facilitates opening of stomatal aperture?

Functional megaspore in an angiosperm develops into

Alexander Von Humbolt described for the first time

Which of the following components provides sticky character to the bacterial cell?

Two plano-concave lenses $(1$ and $2)$ of glass of refractive index $1.5$ have radii of curvature $25 \,cm$ and $20 \,cm$. They are placed in contact with their curved surface towards each other and the space between them is filled with liquid of refractive index $4/3$. Then the combination is

Correct formula of the complex formed in the brown ring test for nitrates is

For the reaction $H _{2}( g )+ Br _{2}( g ) \rightarrow 2 HBr ( g )$, the experiment data suggested that $r = k \left[ H _{2}\right]\left[ Br _{2}\right]^{1 / 2} .$ The molecularity and order of the reaction are respectively:

Two blocks A and B of masses 3m and m respectively are connected by a massless and inextensible string. The whole system is suspended by a massless spring as shown in figure. The magnitudes of acceleration of A and B immediately after the string is cut, are respectively

Two Polaroids P₁ and P₂ are placed with their axis perpendicular to each other. Unpolarised light l₀ is incident on P₁. A third polaroid P₃ is kept in between P₁ and P₂ such that its axis makes an angle 45º with that of P₁. The intensity of transmitted light through P₂ is