List of top Physics Questions

A cube of side 'a' has point charges +Q located at each of its vertices except at the origin where the charge is -Q. The electric field at the centre of cube is : 

A cell $E_1$ of emf 6 V and internal resistance 2 Ω is connected with another cell $E_2$ of emf 4 V and internal resistance 8 Ω (as shown in the figure). The potential difference across points X and Y is : 

In the given figure, a mass M is attached to a horizontal spring which is fixed on one side to a rigid support. The spring constant of the spring is k. The mass oscillates on a frictionless surface with time period T and amplitude A. When the mass is in equilibrium position, another mass m is gently fixed upon it. The new amplitude of oscillation will be : 

A perfect gas undergoes a cyclic process ABCA. A→B: Isothermal expansion ($V_1 \to 2V_1$). B→C: Isobaric compression to $V_1$. C→A: Isochoric change to $P_1$. Total work done is :

If the velocity-time graph has the shape AMB (where M is a peak), what would be the shape of the corresponding acceleration-time graph ? 

A common transistor radio set requires 12 V (D.C.). The D.C. source is constructed using a transformer and a rectifier circuit operated at 220 V (A.C.). The number of turns of secondary coil are 24, then the number of turns of primary are _________. (Assume ideal transformer)
An audio signal $v_m = 20 \sin 2\pi(1500t)$ amplitude modulates a carrier $v_c = 80 \sin 2\pi(100,000t)$. The value of percent modulation is ________
A resonance circuit having inductance and resistance $2 \times 10^{-4}$ H and $6.28$ Ω respectively oscillates at 10 MHz frequency. The value of quality factor of this resonator is __________.
An electromagnetic wave of frequency 5 GHz, is travelling in a medium whose relative electric permittivity and relative magnetic permeability both are 2. Its velocity in this medium is ________ × 10⁷ m/s.
An unpolarized light beam is incident on the polarizer of a polarization experiment and the intensity of light beam emerging from the analyzer is measured as 100 Lumens. Now, if the analyzer is rotated around the horizontal axis (direction of light) by 30° in clockwise direction, the intensity of emerging light will be ________ Lumens.
An inclined plane is bent in such a way that the vertical cross-section is given by $y = x^2 / 4$. If the upper surface is rough with $\mu = 0.5$, the maximum height in cm at which a stationary block will not slip downward is _________ cm.
In a YDSE, width of one slit is three times the other. Amplitude is proportional to slit-width. Find the ratio $I_{max}/I_{min}$.
A ball with a speed of 9 m/s collides with another identical ball at rest. After the collision, the direction of each ball makes an angle of 30° with the original direction. The ratio of velocities of the balls after collision is x : y, where x is _________
A hydraulic press can lift 100 kg when a mass 'm' is placed on the smaller piston. It can lift _________ kg when the diameter of the larger piston is increased by 4 times and that of the smaller piston is decreased by 4 times keeping the same mass 'm' on the smaller piston.
The coefficient of static friction between a wooden block of mass 0.5 kg and a vertical rough wall is 0.2. The magnitude of horizontal force that should be applied on the block to keep it adhere to the wall will be _________ N. [ g = 10 ms⁻² ]
Statement I : Two photons having equal linear momenta have equal wavelengths. Statement II : If the wavelength of photon is decreased, momentum and energy will also decrease.
If an emitter current is changed by 4 mA, the collector current changes by 3.5 mA. The value of β will be :
Two equal capacitors are first connected in series and then in parallel. The ratio of the equivalent capacities in the two cases will be :
The focal length $f$ is related to the radius of curvature $r$ of the spherical convex mirror by :
If Y, K and η are the values of Young's modulus, bulk modulus and modulus of rigidity of any material respectively. Choose the correct relation for these parameters.
A current through a wire depends on time as $i = \alpha_0 t + \beta t^2$ where $\alpha_0 = 20 \text{ A/s}$ and $\beta = 8 \text{ As}^{-2}$. Find the charge crossed through a section of the wire in 15 s.
Match List I with List II.
List I: (a) Isothermal (b) Isochoric (c) Adiabatic (d) Isobaric.
List II: (i) Pressure constant (ii) Temperature constant (iii) Volume constant (iv) Heat content constant.
Two stars of masses $m$ and $2m$ at a distance $d$ rotate about their common centre of mass in free space. The period of revolution is :
Four identical particles of equal masses 1 kg made to move along the circumference of a circle of radius 1 m under the action of their own mutual gravitational attraction. The speed of each particle will be :
Moment of inertia (M.I.) of four bodies, having same mass and radius, are reported as ; $I_1$ = M.I. of thin circular ring about its diameter, $I_2$ = M.I. of circular disc about an axis perpendicular to disc and going through the centre, $I_3$ = M.I. of solid cylinder about its axis and $I_4$ = M.I. of solid sphere about its diameter. Then :