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The correct set of four quantum numbers for the valence electron of rubidium atom (Z = 37) is:
A particular station of All India Radio, New Delhi, broadcasts on a frequency of $1,368 \text{ kHz}$ (kilohertz). The wavelength of the electromagnetic radiation emitted by the transmitter is: [speed of light, $c = 3.0 \times 10^8 \text{ m s}^{-1}$]
An object of mass $500 \text{ g}$ initially at rest is acted upon by a variable force whose $x$-component varies with $x$ in the manner shown. The velocities of the object at the points $x=8 \text{ m}$ and $x=12 \text{ m}$ would have the respective values of nearly:
An ideal gas at $0^\circ\text{C}$ and atmospheric pressure $P$ has volume $V$. The percentage increase in its temperature needed to expand it to $3V$ at constant pressure is:
Incorrect set of quantum numbers from the following is:
How many electrons can fit in the subshell for which n = 3 and l = 1?
Two sound waves with wavelengths $5.0 \text{ m}$ and $5.5 \text{ m}$, respectively, propagate in a gas with a velocity of $330 \text{ m/s}$. How many beats per second can we expect?
A $100 \text{ g}$ iron ball having velocity $10 \text{ m/s}$ collides with a wall at an angle $30^\circ$ and rebounds with the same angle. If the period of contact between the ball and wall is $0.1 \text{ second}$, then the force experienced by the wall is:
Three vessels of equal capacity have gases at the same temperature and pressure. The first vessel contains helium (monoatomic), the second contains fluorine (diatomic) and the third contains sulfur hexafluoride (polyatomic). The correct statement, among the following, is:
Which one of the following ions is the most stable in aqueous solution? (At no. Ti=22, V=23, Cr=24, Mn=25)
If the rate of the reaction is equal to the rate constant, the order of the reaction is:
Match the following columns and select the correct option. Column-I (a) Pituitary gland (b) Thyroid gland (c) Adrenal gland (d) Pancreas Column-II (i) Grave's disease (ii) Diabetes mellitus (iii) Diabetes insipidus (iv) Addison's disease
At any instant of time $t$, the displacement of any particle is given by $2t-1$ (SI unit) under the influence of the force of $5\text{ N}$. The value of instantaneous power (in SI units) is:
The temperature at which the RMS speed of atoms in neon gas is equal to the RMS speed of hydrogen molecules at $15^\circ\text{C}$ is: (the atomic mass of neon $= 20.2 \text{ u}$, molecular mass of hydrogen $= 2 \text{ u}$)
The potential energy of a long spring when stretched by $2\text{ cm}$ is $U$. If the spring is stretched by $8\text{ cm}$, the potential energy stored in it will be:
Given below are two statements: Statement I: In the RNA world, RNA is considered the first genetic material evolved to carry out essential life processes. RNA acts as a genetic material and also as a catalyst for some important biochemical reactions in living systems. Being reactive, RNA is unstable. Statement II: DNA evolved from RNA and is a more stable genetic material. Its double helical strands being complementary, resist changes by evolving repairing mechanism. In light of the above statements, choose the most appropriate answer from the options given below:
A bomb of $12 \text{ kg}$ explodes into two pieces of masses $4 \text{ kg}$ and $8 \text{ kg}$. The velocity of $8 \text{ kg}$ mass is $6 \text{ m/sec}$. The kinetic energy of the other mass is:
A deficiency in which of the following vitamins leads to a decrease in red blood cell (RBC) production?
The following graph represents the T-V curves of an ideal gas (where T is the temperature and V the volume) at three pressures $P_1, P_2$ and $P_3$ compared with those of Charles's law represented as dotted lines. Then the correct relation is:
A particle of mass $m$ is driven by a machine that delivers a constant power of $k$ watts. If the particle starts from rest, the force on the particle at the time $t$ is: