List of top Physics Questions

A light ray passes from mineral A to mineral B having refractive indices of 1.750 and 1.430, respectively. The limiting value of angle of incidence above which the light ray undergoes total internal reflection is ______________ degree (rounded off to one decimal place).
Assume: (i) geothermal gradient = 25°C/km in the crust, (ii) density of the crustal rocks = 3000 kg/m\(^3\), and (iii) acceleration due to gravity = 10 m/s\(^2\). Based on these values, the lithostatic pressure at a point where temperature is 400°C will be ___________MPa.
The limiting molar conductivity of La\(^{3+}\) and Cl\(^{-}\) ions in aqueous medium at 298 K are 209.10 $\times 10^{-4}$ and 76.35 $\times 10^{-4}$ S m\(^2\) mol\(^{-1}\), respectively. The transport number of Cl\(^{-}\) in an infinitely dilute aqueous solution of LaCl\(_3\) at 298 K is ................. (Round off to two decimal places)
(R)-2-methyl-1-butanol has a specific rotation of +13.5°. The specific rotation of 2-methyl-1-butanol containing 40% of the (S)-enantiomer is ................. (Round off to one decimal place)
For three non-coplanar vectors a, b and c, the expression a $\cdot$ (b $\times$ c) can be written as
An infinitely long solenoid of radius \( r \) and number of turns per unit length \( n \) carries a steady current \( I \). The ratio of the magnetic fields at a point on the axis of the solenoid to a point \( r/2 \) from the axis is ..............
The refractive index of a liquid relative to air is 1.5. Calculate the ratio of the real depth to the apparent depth when the liquid is taken in a beaker.
Which one of the following remains unchanged when light waves enter water from air?
In a simple microscope, .............
If escape velocity one earth surface is 11.1 km/hr then find the escape velocity on the moon surface if mass of moon is \(\frac{1}{81}\) times of the mass of the earth and radius is \(\frac{1}{4}\) times radius of earth
The current in the $1\Omega$ resistor shown in the circuit is
In a common base mode of a transistor, the collector current is $5.488\, mA$ for an emitter current of $5.60\, mA$. The value of the base current amplification factor $(\beta)$ will be
The equivalent capacitance of the combination of the capacitors is
The half-life period and the mean life period of a radioactive element are denoted respectively by $T_h$ and $T_m$. Then
If the kinetic energy of a free electron doubles, it�s de-Broglie wavelength changes by the factor
In amplitude modulation, the amplitude of carrier wave is $A_c$ and that of the modulating signal is $A_m$. In practice, the ratio of to $A_m$ to $A_c$ is kept less than or equal to one, to avoid
Consider a pair of insulating blocks with thermal resistances $R_1$ and $R_2$ as shown in the figure. The temperature $\theta$ at the boundary between the two blocks is
A conducting wire frame is placed in a magnetic field which is directed into the paper. The magnetic field is increasing at a constant rate. The directions of induced current in wires $AB$ and $CD$ are
The work done by an uniform magnetic field, on a moving charge is
A solid sphere is rotating in free space. If the radius of the sphere is increased keeping mass same which one of the following will not be affected ?
In Young's double slit experiment, the central point on the screen is
Two thin lenses are in contact and the focal length of the combination is $80\, cm$. If the focal length of one lens is $20 \,cm$, then the power of the other lens will be
A person swims in a river aiming to reach exactly on the opposite point on the bank of a river. His speed of swimming is $0.5\, m/s$ at an angle of $120^?$ with the direction of flow of water. The speed of water is
The Young?? modulus of a perfectly rigid body is
A mass of $0.5\, kg$ moving with a speed of $1.5\, m/ s$ on a horizontal smooth surface, collides with a nearly weightless spring of force constant $k = 50\, N/m$. The maximum compression of the spring would be