List of practice Questions

If a street light of mass $M$ is suspended from the end of a uniform rod of length $L$ in different possible patterns as shown in figure, then :

${ }_{92}^{238} U$ has $92$ protons and $238$ nucleons. It decays by emitting an alpha particle and becomes:

An amplifier has a voltage gain $A_{v}=1000$. The voltage gain in $dB$ is :

When a $p-n$ junction diode is reverse biased, then

Two spheres of same size, one of mass $2\, kg$ and another of mass $4 \,kg$, are dropped simultaneously from the top of Qutab Minar (height $=72\, m$ ). When they are $1 \,m$ above the ground, the two spheres have the same :

A boat at anchor is rocked by waves whose crests are $100\, m$ apart and velocity is $25\, m/\sec$. The boat bounces up once in every

A leaf which contains only green pigments, is illuminated by a laser light of wavelength $0.6328\, \mu m$. It would appear to be :

In refraction, light waves are bent on passing from one medium to the second medium, because in the second medium

Thymine is

$K_2Cr_2O_7$ is used as primary standard in volumetric analysis. It has a good solubility in water.

Isopropyl benzene on air oxidation in the presence of dilute acid gives

Lysine is least soluble in water in the $pH$ range

Molecular nitrogen is less reactive than molecular oxygen. The bond length of $N_2$ is shorter than that of oxygen.

For the Daniel cell, $Zn\left| Zn^{2+}\right|\left| Cu^{2+}\right| Cu$ with $E_{\text{cell}} = 1 . 1\, V$, the application of opposite potential greater than $1 . 1\, V$ results into flow of electron from cathode to anode. $Zn$ is deposited at anode and $Cu$ is dissolved at cathode.

$Fe^{3+}$ can be used for coagulation of $As_2S_3$ sol. $Fe^{3+}$ reacts with $As_2S_3$ to give $Fe_2S_3$.

Change in colour of acidic solution of potassium dichromate by breath is used to test drunken drivers. Change in colour is due to complexation of alcohol with potassium dichromate.

An ideal gas is allowed to expand both reversibly and irreversibly in an isolated system. If $T_i$ is the initial temperature and $T_f$ is the final temperature, which of the following statements is correct ?

Which one of the following sets of ions represents a collection of isoelectronic species ?

After 2 h $\frac{1}{16} th $ of initial amount of a certain radioactive isotope remains undecayed. The half-life of the isotope is

$10\, g$ of ice at $0^{\circ}\,C$ is mixed with $100\, g$ of water at $50^{\circ}\,C$. What is the resultant temperature of mixture?

A bomb explodes on the moon. How long will it take for the sound to reach the earth?

Which of the following is the national bird of India?

Which RNA is short lived

VNTR stands for

The best milch breed in the world is