List of top Physics Questions

The resistance of a wire at room temperature $ 30{}^\circ C $ is found to be $ 10\,\Omega $ . Now to increase the resistance by 10%, the temperature of the wire must be [The temperature coefficient of resistance of the material of the wire is $ 0.002/{}^\circ C $ ]
A mass of $2.0\, kg$ is put on a flat pan attached to a vertical spring fixed on the ground as shown in the figure. The mass of the spring and the pan is negligible. When pressed slightly and released the mass executes a simple harmonic motion . The spring constant is $200\, N/m$ . What should be the minimum amplitude of the motion so that the mass gets detached from the pan (take $g = 10 \,m /s^2 $).
A hollow cylinder has a charge $q$ coulomb within it. If $\phi$ is the electric flux in units of voltmeter associated with the curved surface $B$, the flux linked with the plane surface $A$ in units of voltmeter will be-
A body is released from a great height falls freely towards the earth. Another body is released from the same height exactly a second latter. Then the separation between two bodies, $2\,s$ after the release of the second body is, nearly
Force per unit length between long parallel wires in the circuit is $3.6 \times 10^{-3} \, N \, m^{-1}$. Resistance of the circuit is
A charge $Q$ is to be divided into two parts, $q$ and $(Q- q)$, such that force between them is maximum. Then
If the diameter of a capillary tube is doubled, the rate of flow ofliquid increases
The normal atmospheric pressure can support water column of height L which is, (given density of mercury = $13600\, kg\, m^{-3}$)
In an interference experiment, when a glass plate of refractive index 1.5 is introduced in the path of one of the beams; fringes are displaced by $x$. When the glass plate is replaced by another transparent plate of same thickness, shift in the fringe is $ \frac{3}{2} x .$ Refractive index of $2^{nd}$ transparent plate is
A bulb is kept at a depth h inside water of refractive index $' n' $. Area of the bright patch on the water surface is
The ratio of forces between two point charges in the two cases when their separation is halved and when it is doubled, is
To increase the angular width of interference fringes
The speed of electromagnetic radiation in vacuum
$A, B$ and $C$ are three voltmeters of resistances $4000 \, \Omega , 6000 \Omega$ and $12000 \Omega$. When a potential difference? is applied between $X$ and $Y$, voltmeter readings are $V_A, V_B$ and $V_C$. Then
The kinetic energy of the photoelectrons increases by $0.52 \, eV$ when the wavelength of incident light is changed from $500 \, nm$ to another wavelength which is approximately
The capacitance of the Earth considered as a conducting sphere of radius $6408 \, km$ is
Two points separated by a distance of 0.1 mm can just be observed using a microscope when light $\lambda = 600\: nm$ is used. If light of wavelength 480 nm is used, this limit of resolution becomes
An object radiates at temperature $127^{\circ} C$. Temperature. at which radiates 16 times more is
In Young's double slit experiment, intensity at a bright fringe is $I_0$. One of the slits is closed. Intensity at the same position is
A spring balance carries a load. When the load is pulled aside so that the balance makes an angle of $30^{\circ}$ with the vertical, the balance reads $4 \, kg\, wt$. The mass of the load is
An open $ U $ -tube contains mercury. When $ 11.2 \,cm $ of water is poured into one of the arms of the tube, how high does the mercury rise in the other arm from its initial unit ?
We consider a thermodynamic system. If $ \Delta U $ represents the increase in its internal energy and $ W $ the work done by the system, which of the following statements is true ?
A particle moving along $x$ -axis has acceleration $f$, at time $t$, given by $f = f _{0}\left(1-\frac{ t }{ T }\right)$, where $f _{0}$ and $T$ are constants. The particle at $t =0$ has zero velocity. In the time interval between $t =0$ and the instant when $f =0$, the particle's velocity $\left( v _{ x }\right)$ is:
Assuming the sun to have a spherical outer surface of radius r, radiating like a black body at temperature $t^{\circ} C$, the power received by a unit surface, (normal to the incident rays) at distance $R$ from the centre of the Sun is:- Where $\sigma$ is the Stefan's Constant.
$A$ vertical spring with force constant $k$ is fixed on a table. $A$ ball of mass m at a height h above the free upper end of the spring falls vertically on the spring so that the spring is compressed by a distance $d$ . The net work done in the process is