List of top Physics Questions

A radio can tune to any station in $6\, MHz$ to $10\, MHz$ band The value of corresponding wavelength bandwidth will be :
The equation $\lambda=\frac{1227}{ x } nm$ can be used to find the de-Brogli wavelength of an electron In this equation $x$ stands for : Where, $m =$ mass of electron $P =$ momentum of electron $K =$ Kinetic energy of electron $V=$ Accelerating potential in volts for electron
\(B_X\) and \(B_Y\) are the magnetic field at the centre of two coils of two coils \(X\) and \(Y\) respectively, each carrying equal current If coil \(X\) has \(200\) turns and \(20\, cm\) radius and coil \(Y\) has \(400\) turns and \(20 \,cm\) radius, the ratio of \(B_X\) and \(B_Y\) is
As shown in the figure, after passing through the medium 1. The speed of light v2 in medium 2 will be: (Given \(c = 3 \times 10^8 ms^{-1}\))
speed of light v2 in medium 2
As shown in the figure, a metallic rod of linear density \(0.45\ kg m^{-1}\) is lying horizontally on a smooth incline plane which makes an angle of 45° with the horizontal. The minimum current flowing in the rod required to keep it stationary, when \(0.15 T\) magnetic field is acting on it in the vertical upward direction, will be: {Use \(g = 10 m/s^2\)}
metallic rod of linear density
In normal adjustment, for a refracting telescope, the distance between objective and eye piece is $30\,cm$ The focal length of the objective, when the angular magnification of the telescope is 2, will be:
The total charge on the system of capacitance $C _1=1\, \mu F , C _2=2 \,\mu F , C _3=4 \,\mu F $ and $C _4=3\, \mu F$ connected in parallel is (Assume a battery of $20 \,V$ is connected to the combination)
A charge particle is moving in a uniform magnetic field $(2 \hat{ i }+3 \hat{ j }) T$ If it has an acceleration of $(\alpha \hat{i}-4 \hat{j}) m / s ^2$, then the value of $\alpha$ will be
The half life period of a radioactive substance is 60 days The time taken for $\frac{7}{8}$ th of its original mass to disintegrate will be :
The current sensitivity of a galvanometer can be increased by: 
(A) decreasing the number of turns 
(B) increasing the magnetic field 
(C) decreasing the area of the coil 
(D) decreasing the torsional constant of the spring Choose the most appropriate answer from the options given below:
The magnetic field of a plane electromagnetic wave is given by $\vec{ B }=2 \times 10^{-8} \sin \left(05 \times 10^3 x +15 \times 10^{11} t \right) \hat{ j } T$ The amplitude of the electric field would be

The current \(I\) in the given circuit will be

The disintegration rate of a certain radioactive sample at any instant is $4250$ disintegrations per minute $10$ minutes later, the rate becomes $2250 $ disintegrations per minute The approximate decay constant is : (Take $\log _{10} 188=0274$ )
\(7\) mole of certain monoatomic ideal gas undergoes a temperature increase of \(40\, K\) at constant pressure The increase in the internal energy of the gas in this process is (Given \(R =83\, JK ^{-1}\, mol ^{-1}\))
A parallel beam of light of wavelength $900 \,nm$ and intensity $100 \,Wm ^{-2}$ is incident on a surface perpendicular to the beam Tire number of photons crossing $1 \,cm ^2$ area perpendicular to the beam in one second is :
A water drop of radius $1 \,cm$ is broken into $729$ equal droplets If surface tension of water is $75 \,dync / cm$, then the gain in surface energy upto first decimal place will be : [Given $\pi=314]$
The power of a lens (biconvex) is \(1.25 m^{–1}\) in particular medium. Refractive index of the lens is \(1.5\), and the radii of curvature are \(20 cm\) and \(40 cm\), respectively. The refractive index of surrounding medium

An inductor of 0.5 mH, a capacitor of 200 μF and a resistor of 2 Ω are connected in series with a 220 V ac source. If the current is in phase with the emf, the frequency of ac source will be ______ × 102 Hz

A vessel contains 16 g of hydrogen and 128 g of oxygen at standard temperature and pressure. The volume of the vessel in cm3 is:

In a carnot engine, the temperature of reservoir is 527°C and that of sink is 200 K. If the work done by the engine when it transfers heat from reservoir to sink is 12000 kJ, the quantity of heat absorbed by the engine from reservoir is _____ \(× 10^6\) J.

A block of mass M placed inside a box descends vertically with acceleration ‘a’.The block exerts a force equal to one-fourth of its weight on the floor of the box.
The value of ‘a’ will be
A radioactive sample decays 7/8 times its original quantity in 15 minutes. The half-life of the sample is
An npn transistor with current gain \(β = 100\) in common emitter configuration is shown in the figure. The output voltage of the amplifier will be
npn transistor with current gain

A potential barrier of 0.4 V exists across a p-n junction. An electron enters the junction from the n-side with a speed of 6.0 × 105 ms–1. The speed with which electrons enters the p side will be
\(\frac{x}{3} × 10^5\) ms-1
the value of x is _________.
(Give mass of electron = 9 × 10–31 kg, charge on electron = 1.6 × 10–19 C)

In a double slit experiment with monochromatic light, fringes are obtained on a screen placed at some distance from the plane of slits. If the screen is moved by 5 × 10–2 m towards the slits, the change in fringe width is 3 × 10–3 cm. If the distance between the slits is 1 mm, then the wavelength of the light will be _______ nm.