List of practice Questions

The $ 'd' $ orbital involved in the hybridisation in the $ PCl_{5} $ molecule is

When a galvanometer is shunted by resistance S, its current capacity increases n times. If the same galvanometer is shunted by another resistance S', its current capacity will increase by n' is given by

The critical angle for total internal reflection in diamond is $ 24.5^{\circ} $ . The refractive index of the diamond is

An electrical cable having a resistance of $0.2 \,\Omega$ delivers $10\,kw$ at $200\,V\, D.C$. to a factory. What is the efficiency of transmission?

Huygens principle of secondary wavelets may be used to

Which out of following, cannot produce two coherent sources?

The term quaternary structure is used in the context of

In plants, water supply is due to

Somaclonal variation appears in plants

Which of the following is true?

Which of the following is correct?

A soap bubble of radius $r$ is blown up to form a bubble of radius $2 r$ under isothermal conditions. If $T$ is the surface tension of soap solution, the energy spent in the blowing

Pineapple fruit develops from

The equation $\sqrt{3}\, \sin \,x+\cos\,x = 4$ has

The angle between the lines joining the foci of an ellipse to one particular extremity of the minor axis is $90^{\circ}$ The eccentricity of the ellipse is

Assuming earth to be an inertial frame, an example for inertial frame observer is

In a monoecious plant

The colloidal solution in which both the dispersed phase and dispersion medium arc liquids called

If If $n =(2020)$, then $\frac {1}{\log_2n}+\frac {1}{\log_3n}+\frac {1}{\log_4n}+............+\frac {1}{\log_{2020} n}$

A block $B$ is pushed momentarily along a horizontal surface with an initial velocity $v$ . If $\mu$ is the coefficient of sliding friction between $B$ and the surface, block $B$ will come to rest after a time

The frequency of a light wave in a material is $2 \times 10^{14} Hz$ and wavelength is $5000\, ?$. The refractive index of material will be

Two radioactive substances $A$ and $B$ have decay constants $5\, \lambda$ and $\lambda$ respectively. At $t=0$ they have the same number of nuclei. The ratio of number of nuclei of $A$ to those of $B$ will be $\left(\frac{1}{e}\right)^{2}$ after a time interval

In a mass spectrometer used for measuring the masses of ions, the ions are initially accelerated by an electric potential $V$ and then made to describe semicircular paths of radius $R$ using a magnetic field $B$. If $V$ and $B$ are kept constant, the ratio $\left(\frac{\text { charge on the ion }}{\text { mass of the ion }}\right)$ will be proportional to

The displacement of a particle executing $SHM$ is given by $y=5 \sin \left(4 t+\frac{\pi}{3}\right)$ If $T$ is the time period and the mass of the particle is $2\, g$, the kinetic energy of the particle when $t = T / 4$ is given by

Which of the following cannot be speed-time graph ?