List of top Physics Questions

An ideal gas at \(27^{\circ}\)C is compressed adiabatically to \((\frac{8}{27})\) of its original volume. If \(γ = 5/3\), then the rise in temperature of a gas is
A progressive wave of frequency 50 Hz is travelling with velocity 350 m/s through a medium. The change in phase at given time interval of 0.01s is
A liquid is at rest in a container. In a sphere of influence, the liquid molecule at its centre is
A black rectangular surface of area 'A' emits energy 'E' per second at \(27^{\circ}\)C. If length and breadth is reduced to half of its initial value and temperature is raised to \(327^{\circ}\)C then energy emitted per second becomes
Rate of flow of heat through a cylindrical rod is '\(H_1\)'. The temperature at the ends of the rod are \(T_1\) and \(T_2\). If all the dimensions of the rod become double and the temperature difference remains the same and if the rate of flow of heat becomes '\(H_2\)' then \(H_2 =\)
Water flows through a horizontal pipe at a speed 'V'. Internal diameter of the pipe is 'd'. If the water is emerging at a speed '\(V_1\)' then the diameter of the nozzle is
A closed pipe containing liquid showed a pressure \(P_1\) by gauge. When the valve was opened, pressure was reduced to \(P_2\). The speed of water flowing out of the pipe is (\(ρ\)=density of water)
The energy spectrum of a black body exhibits a maximum around a wavelength '\(λ\)'. The temperature of the black body is now changed such that the energy is maximum around a wavelength \(2λ/3\). The power radiated by the black body will now increase by a factor
A particle is moving with constant angular acceleration \(4\,\text{rad/s}^2\) in circular path. At what time the magnitudes of its tangential acceleration and centripetal acceleration will be equal ?
The masses and radii of the earth and moon are \(M_1\), \(R_1\) and \(M_2\), \(R_2\) and respectively, Their centres are at a distance 'd' apart. The minimum speed with which body of mass 'm' should be projected from a distance \(2d/3\) from the centre of \(M_1\) so as to escape to infinity is
A Solid sphere has mass M and radius R. Its moment of inertia about a parallel axis passing through a point at a distance R/3 from its centre is
A particle describes a horizontal circle of radius 'r' in conical funnel with smooth inner surface with a speed of \(0.5\) m/s. The height of the plane of the circle from the vertex of the funnel is (acceleration due to gravity, \(g = 10\,\text{m/s}^2\))
A block of mass 'm' moving on a frictionless horizontal surface collides with a spring of spring constant 'K' and compresses it through a distance 'x'. The maximum momentum of the block after collision is
A rectangular block of mass 'm' and cross-sectional area 'A' floats on a liquid of density '\(ρ\)'. It is given a small vertical displacement from equilibrium, it starts oscillating with frequency (g=acceleration due to gravity)
A ball is released from height 'h' which makes perfectly elastic collision with ground. The frequency of periodic vibratory motion is (g=acceleration due to gravity)
A wire has mass \((0.3\pm 0.003)\) gram, radius \((0.5\pm 0.005)\) cm and length \((6\pm 0.06)\) cm. The maximum percentage error in the measurement of density is
Let \(\overset{⃗}{P} = \hat{i}+\hat{j}+\hat{k}\) and \(\overset{⃗}{Q} = -(\hat{i}+\hat{j}+\hat{k})\). The angle between \((\overset{⃗}{P}-\overset{⃗}{Q})\) and \(\overset{⃗}{P}\) is
Two boys are standing at points A and B on ground where distance AB = a. The boy at point B starts running perpendicular to line AB with velocity '\(V_1\)'. The boy at point A starts running simultaneously with velocity 'V' and catches the other boy in time 't'. The value of 't' is
In the logic circuit diagram, when all the four inputs, A, B, C, D are 'one' the outputs \(Y_1\), \(Y_2\), \(Y_3\) are respectively (1, 1, 0). When the inputs A and C are changed to zero and B and D are still 'one', then the outputs \(Y_1\), \(Y_2\), \(Y_3\) are respectively change to
In the hydrogen atom, radii of the first four Bohr orbits are related as
The electron in hydrogen atom is initially in the second excited state. When it finally moves to ground state, the maximum number of spectral lines emitted are
In the diagram shown, the resistance between points A and B is '\(R_1\)' when an ideal diode D is forward biased and is '\(R_2\)' when ideal diode D is reverse biased. The ratio \(R_1/R_2\) is
In common emitter amplifier, a change of \(0.2\) mA in the base current causes a change of \(5\) mA in the collector current. If input resistance is \(2\) k\(\Omega\) and voltage gain is \(75\), the load resistance used in the circuit is
In an LCR series circuit, at resonance,
When a metallic surface is illuminated with a radiation of wavelength '\(λ\)', the stopping potential is 'V'. If the same surface is illuminated with radiation of wavelength \(6λ\), the stopping potential is \((\frac{V}{12})\). The threshold wavelength for the surface is