List of practice Questions

Sea weeds are an important source of
A mass of $ 6 \,kg $ is suspended by a rope of length $ 2\, m $ from a ceiling. A force of $ 50 \,N $ in the horizontal direction is applied at the mid-point of the rope. The angle made by the rope with the vertical, in equilibrium is
An open organ pipe is closed suddenly with the result that the second overtone of the closed pipe is found to be higher in frequency by $ 100 $ than the first overtone of the original pipe. Then the fundamental frequency of the open pipe is
A particle is moving with constant acceleration from $A$ to $B$ in a straight line $AB$. If $u$ and $v$ are the velocities at $A$ and $B$ respectively then its velocity at the midpoint $C$ will be
A thin circular ring of mass m and radius R is rotating about its axis perpendicular to the plane of the ring with a constant angular velocity $\omega$. Two point particles each of mass M are attached gently to the opposite ends of a diameter of the ring. The ring now rotates with an angular velocity $\omega /2$. Then, the ratio m/M is
Two vessels of volumes $16.4\, L$ and $5\,L$ contain two ideal gases of molecular existence at the respective temperature of $27^?C$ and $227^?C$ and exert $1.5$ and $4.1$ atmospheres respectively. The ratio of the number of molecules of the former to that of the latter is
The major product of the reaction between tert-butyl chloride and sodium ethoxide is
An astronomical telescope has an angular magnification of magnitude $5$ for distant objects. The separation between the objective and the eye-piece is $36 \,cm$ and the final image is formed at infinity. The focal length $ {{f}_{o}} $ of the objective and $ {{f}_{e}} $ of the eye-piece are respectively
Electric charge is uniformly distributed along a long straight wire of radius $1\,mm$. The charge per cm length of the wire is $Q$ coulomb. Another cylindrical surface of radius $50 \,cm$ and length $1\, m$ symmetrically encloses the wire. The total electric flux passing through the cylindrical surface is
For a zero order reaction, the plot of concentration of reactant $vs$ time is (intercept refers to concentration axis)
How many amino acids are present in insulin?
How many molecules of $CO_2$ are formed when one milligram of $100\%$ pure $CaCO_3$ is treated with excess hydrochloric acid?
If a body of mass m has to be taken from the surface of earth to a height $h = R$, then the amount of energy required is ($R$ = radius of earth)
If a magnetic dipole of moment $M$ situated in the direction of a magnetic field $B$ is rotated by $180^{\circ}$, then the amount of work done is
If the critical frequency for sky wave propagation is 12 MHz, then the maximum electron density in the ionosphere is
In a Fraunhofer diffraction at single slit of width d with incident light of wavelength 5500 $\mathring {A}$, the first minimum is observed, at angle 30$^{\circ}$. The first secondary maximum is observed at an angle $\theta$
In the preparation of potassium permanganate, pyrolusite $ (Mn{{O}_{2}}) $ is first converted to potassium manganate $ ({{K}_{2}}Mn{{O}_{4}}) $ . In this conversion, the oxidation state of manganese changes from:
Lassaigne?s test (with silver nitrate) is commonly used to detect halogens such as chlorine, bromine and iodine but not useful to detect fluorin because the product $AgF$ formed is
Neopentyl bromide undergoes dehydrohalogenation to give alkenes even though it has no $\beta$- hydrogen. This is due to
The donor atom in EDTA are
The metal that produces red-violet colour in the non-luminous flame is
When chlorobenzene is reacted with acetyl chloride in the presence of anhydrous AICI$_3$, the major product formed is
The coefficient of $x^5$ in the expansion of $(1 + x^2)^5(1 + x)^4$ is
The solution set of $\frac{x+3}{x-2} \le\,2$ is
Some carboxylic acids and their $IUPAC$ names are given below. Which of the following is not correctly matched?