List of top Physics Questions

In a measurement, it is asked to find the modulus of elasticity per unit torque applied on the system. The measured quantity has the dimension of \( [M^a L^b T^c] \). If \( b = 3 \), the value of \( c \) is:
A proton of mass 'mp' has same energy as that of a photon of wavelength 'λ'. If the proton is moving at non-relativistic speed, then ratio of its de Broglie wavelength to the wavelength of photon is.

The center of mass of a thin rectangular plate (fig - x) with sides of length \( a \) and \( b \), whose mass per unit area (\( \sigma \)) varies as \( \sigma = \sigma_0 \frac{x}{ab} \) (where \( \sigma_0 \) is a constant), would be 

 

In the experiment for measurement of viscosity \( \eta \) of a given liquid with a ball having radius \( R \), consider following statements:
A. Graph between terminal velocity \( V \) and \( R \) will be a parabola. 
B. The terminal velocities of different diameter balls are constant for a given liquid. 
C. Measurement of terminal velocity is dependent on the temperature. 
D. This experiment can be utilized to assess the density of a given liquid. 
E. If balls are dropped with some initial speed, the value of \( \eta \) will change.

Given below are two statements: one is labelled as Assertion \(A\) and the other as Reason \(R\): 

Assertion \(A\): A sound wave has higher speed in solids than in gases. 
Reason \(R\): Gases have higher value of Bulk modulus than solids.

Choose the correct nuclear process from the below options:
Consider the following statements: Surface tension arises due to extra energy of the molecules at the interior as compared to the molecules at the surface of a liquid. As the temperature of liquid rises, the coefficient of viscosity increases. As the temperature of gas increases, the coefficient of viscosity increases. The onset of turbulence is determined by Reynolds number. In a steady flow, two streamlines never intersect. Choose the correct answer from the options given below:
Due to the presence of an em-wave whose electric component is given by \( E = 100 \sin(\omega t - kx) \, \text{N/C} \), a cylinder of length 200 cm holds a certain amount of em-energy inside it. If another cylinder of the same length but half the diameter of the previous one holds the same amount of em-energy, the magnitude of the electric field of the corresponding em-wave should be modified as:

A bead of mass \( m \) slides without friction on the wall of a vertical circular hoop of radius \( R \) as shown in figure. The bead moves under the combined action of gravity and a massless spring \( k \) attached to the bottom of the hoop. The equilibrium length of the spring is \( R \). If the bead is released from the top of the hoop with (negligible) zero initial speed, the velocity of the bead, when the length of spring becomes \( R \), would be (spring constant is \( k \), \( g \) is acceleration due to gravity): 

For a particular ideal gas, which of the following graphs represents the variation of mean squared velocity of the gas molecules with temperature?

Which of the following circuits has the same output as that of the given circuit?

A particle of mass \( m \) and charge \( q \) is fastened to one end \( A \) of a massless string having equilibrium length \( l \), whose other end is fixed at point \( O \). The whole system is placed on a frictionless horizontal plane and is initially at rest. If a uniform electric field is switched on along the direction as shown in the figure, then the speed of the particle when it crosses the x-axis is:

If the acceleration due to gravity on the surface of Earth is \( g \), then the acceleration due to gravity on a planet whose diameter is \( \frac{1}{3} \) of that of Earth and same mass as that of Earth is \( g' = ng \), where \( n \) is
A solid sphere rolls without slipping on a horizontal plane. What is the ratio of translational kinetic energy to the rotational kinetic energy of the sphere?
A solid sphere and hollow sphere roll down purely equal distances on the same inclined plane (starting from rest) in time \( t_1 \) and \( t_2 \). Then
The temperature in a city is measured to be 30°C. What is the corresponding temperature in Fahrenheit?
In Young's Double Slit Experiment, monochromatic light of wavelength \( \lambda \) is used. The slits are separated by a distance \( d \), and the screen is placed at a distance \( D \) from the slits. If the fringe width is observed to be \( \beta \), and the distance between the slits and the screen is doubled, what will be the new fringe width?
Find the wavelength in (nm) of incident radiation where the work function is 4.12 eV and the stopping potential is 4V. Given that \( h \nu = 1242 \, \text{eV} \cdot \text{nm} \).
Two charges +7 mC and -4 mC at coordinates (-7, 0, 0) and (7, 0, 0), respectively, find the electrostatic potential energy. \[ \epsilon_0 = 8.85 \times 10^{-12} \, \text{C}^2 \, \text{N}^{-1} \, \text{m}^{-2}. \]
The value of \( E_0 \) is 9.3 V/m and \( c \) is \( 3 \times 10^8 \, \text{m/s} \). Find the value of \( B_0 \).
Find the charge on the capacitor in the steady state. \vspace{1cm} \includegraphics[width=0.7\textwidth]{a.png}
If the angle of prism equals the angle of minimum deviation, and given that the refractive index \( \mu = \sqrt{3} \), then the angle of the prism is:
A proton is moving with a uniform velocity of \( 2 \times 10^8 \, \text{m/s} \) in uniform magnetic and electric fields which are perpendicular to each other. If the electric field is switched off, then the proton moves in a circular path of radius \( 1.6 \times 10^{-5} \, \text{m} \). Then the magnetic field \( B \) is:
Electric flux \( \varphi \) is related with linear charge density \( \lambda \) and surface charge density \( \sigma \) as \( \varphi = \alpha \lambda + \beta \sigma \). Where \( \alpha \) and \( \beta \) are of appropriate dimension. The dimension of \( \frac{\beta}{\alpha} \) is:
Statement 1: Hotter water moves faster than cold water.
Statement 2: Soap water has a higher surface tension than fresh water.