List of practice Questions

The ratio of the amounts of heat developed in the four arms of a balance Wheatstone bridge, when the arms have resistances $P = 100\, \Omega,\,Q = 10\, \Omega,\, R = 300\, \Omega$ and $S = 30\, \Omega$ respectively is
If $z=\frac{1-i \sqrt{3}}{1+i \sqrt{3}}$, then $\arg (z)$ is
If $z$ satisfies the equation $|z|-z=1+2 i$, then $z$ is equal to
Sinusoidal carrier voltage of frequency $1.5\, MHz$ and amplitude $50\, V$ is amplitude modulated by sinusoidal voltage of frequency $10\, kHz$ producing $50 \%$ modulation. The lower and upper side-band frequencies in $kHz$ are
The attenuation in optical fibre is mainly due to
The collector plate in an experiment on photoelectric effect is kept vertically above the emitter plate. Light source is put on and a saturation photo-current is recorded. An electric field is switched on which has a vertically downward direction, then
In the hydrogen atom, the electron is making $6.6 \times 10^{15}$ rps. If the radius of orbit is $0.53 \times 10^{-10}$ m, then magnetic field produced at the centre of the orbit is
In a buffer solution containing equal concentration of $ B^- $ and HB, the $ K_b $ for $ B^- $ is $ 10^{-10} $ . The pH of buffer solution is
The points $(1, 0), (0, 1), (0, 0) $ and $ (2k, 3k),k \neq 0$ are concyclic if $k$ = _____
What is $ [H^+] $ in mol/L of a solution that is $0.20 \,M$ in $ CH_3COONa $ and $0.10 \,M$ in $ CH_3COOH $ ? $ (K_a\, \, for\, \, CH_3COOH = 1.8 \times 10^{-5}) $
Hot water cools from $60^{\circ}C$ to $50^{\circ}C$ in the first $10$ minutes and to $42^{\circ}C$ in the next $10$ minutes. Then the temperature of the surroundings is
Match the animals listed in Column I with their of nature of blood listed in Column II. Choose the answer which gives the correct combination of alphabets of the two columns
A mixture of $CaCl_2$ and $NaCl$ weighing $4.44\, g$ is treated with sodium carbonate solution to precipitate all the calcium ions as calcium carbonate. The calcium carbonate so obtained is heated strongly to get $0.56\, g$ of $CaO$. The percentage of $NaCl$ in the mixture is (Atomic mass of $Ca = 40)$
In Kjeldahl's method, ammonia from $5\, g$ of food neutralizes $30 \,cm^3$ of $0.1\, N$ acid. The percentage of nitrogen in the food is
In the electrolytic refining of Zinc ,.................
: One molar aqueous solution has always higher concentration than one molal. : The molality of a solution depends upon the density of the solution whereas molarity does not.
Infectious proteins are present in
For detecting intensity of light we use
The species which by definition has zero standard molar enthalpy of formation at $298 \,K$ is
Among the following, intensive property is (properties are)
Which one of the following species does not exist under normal conditions?
The area bounded by the curve $ y= \begin{cases} x^2,x<0 & \quad\\ x,x \geq 0 & \quad \\ \end{cases} $ and the line $y = 4$ is
The Young's modulus of brass and steel are respectively $ 1.0\times 10^{11}Nm^{-2} $ and $ 2.0\times 10^{11}Nm^{-2}. $ .A brass wire and a steel wire of the same length are extended by $1 \,mm$ each under the same force. If radii of brass and steel wires are $R_B$ and $R_S$ respectively, then
In human female the blastocyst
The terminal velocity of a rain drop of radius $r$ is $ 2\,cm\,s^{-1}$ . If eight such identical drops combine to form a single large drop, the terminal velocity would be