List of top Physics Questions

A uniform chain of length 3 meter and mass 3 kg overhangs a smooth table with 2 meter laying on the table. If k is the kinetic energy of the chain in joule as it completely slips off the table, then the value of k is _________.
(Take \(g = 10 \text{ m/s}^2\))

Consider a badminton racket with length scales as shown in the figure. 

If the mass of the linear and circular portions of the badminton racket are same (M) and the mass of the threads are negligible, the moment of inertia of the racket about an axis perpendicular to the handle and in the plane of the ring at, \(\frac{r}{2}\) distance from the end A of the handle will be _________ \(Mr^2\). 
 

A soap bubble of radius 3 cm is formed inside the another soap bubble of radius 6 cm. The radius of an equivalent soap bubble which has the same excess pressure as inside the smaller bubble with respect to the atmospheric pressure is _________ cm.
Two travelling waves produces a standing wave represented by equation. \(y = 1.0 \text{ mm} \cos(1.57 \text{ cm}^{-1})x \sin(78.5 \text{ s}^{-1})t\). The node closest to the origin in the region \(x>0\) will be at \(x = \)_________ cm.
Two short magnetic dipoles \(m_1\) and \(m_2\) each having magnetic moment of \(1 \text{ Am}^2\) are placed at point O and P respectively. The distance between OP is 1 meter. The torque experienced by the magnetic dipole \(m_2\) due to the presence of \(m_1\) is _________ \(\times 10^{-7} \text{ Nm}\).
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The electric field in a plane electromagnetic wave is given by
\(\vec{E} = 200 \cos \left[ \left( \frac{0.5 \times 10^3}{\text{m}} \right) x - (1.5 \times 10^{11} \frac{\text{rad}}{\text{s}} \times t) \right] \frac{\text{V}}{\text{m}} \hat{j}\).
If this wave falls normally on a perfectly reflecting surface having an area of \(100 \text{ cm}^2\). If the radiation pressure exerted by the E.M. wave on the surface during a 10 minute exposure is \(\frac{x}{10^9} \frac{\text{N}}{\text{m}^2}\). Find the value of \(x\).
White light is passed through a double slit and interference is observed on a screen 1.5 m away. The separation between the slits is 0.3 mm. The first violet and red fringes are formed 2.0 mm and 3.5 mm away from the central white fringes. The difference in wavelengths of red and violet light is _________ nm.
An amplitude modulated wave is represented by \(C_m(t) = 10(1 + 0.2 \cos 12560 t) \sin(111 \times 10^4 t)\) volts. The modulating frequency in kHz will be _________.
Two spherical balls having equal masses with radius of 5 cm each are thrown upwards along the same vertical direction at an interval of 3 s with the same initial velocity of 35 m/s, then these balls collide at a height of _________ m.
(take \(g = 10 \text{ m/s}^2\))
Moment of inertia of a square plate of side l about the axis passing through one of the corner and perpendicular to the plane of square plate is given by :

The resultant of these forces \(\vec{OP}, \vec{OQ}, \vec{OR}, \vec{OS}\) and \(\vec{OT}\) is approximately ________ N. 
[Take \(\sqrt{3} = 1.7, \sqrt{2} = 1.4\). Given \(\hat{i}\) and \(\hat{j}\) unit vectors along x, y axis] 

 

If E and H represents the intensity of electric field and magnetising field respectively, then the unit of E/H will be :
An ideal gas is expanding such that \(PT^3 = \text{constant}\). The coefficient of volume expansion of the gas is :
A balloon carries a total load of 185 kg at normal pressure and temperature of 27°C. What load will the balloon carry on rising to a height at which the barometric pressure is 45 cm of Hg and the temperature is -7°C. Assuming the volume constant ?

The variation of displacement with time of a particle executing free simple harmonic motion is shown in the figure. 
The potential energy U(x) versus time (t) plot of the particle is correctly shown in figure : 

Calculate the amount of charge on capacitor of 4 \(\mu\)F. The internal resistance of battery is 1 \(\Omega\): 

 

A uniformly charged disc of radius R having surface charge density \(\sigma\) is placed in the xy plane with its center at the origin. Find the electric field intensity along the z-axis at a distance Z from origin :
Two ions of masses 4 amu and 16 amu have charges +2e and +3e respectively. These ions pass through the region of constant perpendicular magnetic field. The kinetic energy of both ions is same. Then :

A bar magnet is passing through a conducting loop of radius R with velocity v. The radius of the bar magnet is such that it just passes through the loop. The induced e.m.f. in the loop can be represented by the approximate curve : 

Electric field in a plane electromagnetic wave is given by E = 50 sin(500x - 10 \(\times\) 10\(^{10}\)t) V/m. The velocity of electromagnetic wave in this medium is : (Given C = speed of light in vacuum)
An object is placed beyond the centre of curvature C of the given concave mirror. If the distance of the object is \(d_1\) from C and the distance of the image formed is \(d_2\) from C, the radius of curvature of this mirror is :

Find the distance of the image from object O, formed by the combination of lenses in the figure : 

 

In a photoelectric experiment, increasing the intensity of incident light :
There are 10\(^{10}\) radioactive nuclei in a given radioactive element. Its half-life time is 1 minute. How many nuclei will remain after 30 seconds ? (\(\sqrt{2}\) = 1.414)

A circuit is arranged as shown in figure. The output voltage \(V_o\) is equal to ________ V.