List of top Physics Questions

In series LCR circuit \(R = 10\,\Omega\) and impedance is \(30\,\Omega\). An r.m.s. voltage \(210\) V, is applied across the circuit. The true power consumed in AC circuit is
Two coils P and S have a mutual inductance of (\(π\)) mH. The secondary coil S has resistance \(4\,\Omega\) and self inductance \((60/π)\) mH. If the current in the primary is \(I_p = 12sin(50πt)\), then the maximum value of the current induced in coil S is [Take \(π^2 = 10\)]
When a.c. source is connected across a pure capacitor, the correct phase relation between current and emf is shown in figure.
Light travels a distance 'x' in time '\(t_0\)' in air and '\(4x\)' in time '\(t_1\)' in another denser medium. The critical angle for this medium is
A current carrying circular coil of radius 'R' produces magnetic field \(B_1\) at an axial point P at a distance 'x' from its centre and \(B_2\) at point Q placed at its centre respectively . If \(B_2 = 8B_1\), the value of x is
When a galvanometer is shunted by a resistance 'S', its current capacity increases 'n' times. If the same galvanometer is shunted by another resistance '\(S^1\)', its current capacity will increase to '\(n^1\)'. The value of n in terms of \(n^1\), S and \(S^1\) is
A parallel plate air capacitor has capacity 'C' farad, potential 'V' volt and energy 'E' joule. When the gap between the plates is completely filled with dielectric
The resistances in the two gaps of a balanced meter bridge are 'X' \(\Omega\) and '3X' \(\Omega\) respectively. If the resistances are interchanged the balance point shifts by
The magnetic induction produced inside an ideal solenoid, depends on which of the following quantities ?
(a) number of turns per unit length.
(b) radius of the wire.
(c) current flowing throught it.
(d) permeability of the medium.
In an oscillating LC circuit the maximum charge on the capacitor is Q. When the energy is stored equally between the electric and magnetic fields, the charge on the capacitor (q) is
A body sends a wave \(150\) mm long through medium P and \(0.30\) m long in medium Q. If velocity of the wave in medium P is \(80\,\text{cm s}^{-1}\), the velocity of wave in medium Q is
A particle of mass 'm' and charge 'q', initially at rest, is accelerated by a uniform electric field 'E' through a distance 'D' and is then allowed to approach a fixed static charge 'Q' of the same sign. The distance of the closest approach of the charge q is
[ \(ε_0\) = permittivity of free space ]
An uniformly charged thin spherical shell of radius 'R' has uniform surface charge density '\(σ\)'. It is made of two hemispherical identical shells held together by pressing them with force 'F' as shown. F is proportional to
[\(ε_0\) = permittivity of free space]
Two equal positive charges each of value 'q' are placed at points A and B, where \(AB = 3x\). A third charge \(-3q\) is placed at point C at a distance \(x\) from A on AB. The potential energy of the system is nearly (\(ε_0\) = permittivity of free space)
The equation of a progressive wave is given by \(y = 6cos(100t-4x)\) where \(y\) is in \(μ\text{m}\), \(x\) in metre and \(t\) in second. The ratio of the maximum particle velocity to the velocity of wave is
Two waves of same frequency (\(n\)) approaching each other with same velocity of \(18\) m/s interfere. The distance between two consecutive antinodes is
A spring force constant \(180\) N/m is loaded with a mass \(0.2\) kg. The amplitude of oscillations is \(4\) cm. When mass comes to equilibrium position, its velocity is
A particle executing linear S.H.M. has velocities \(V_1\) and \(V_2\) at distance \(x_1\) and \(x_2\) respectively, from the mean position, its angular velocity is
In a resonance tube open at one end, the end correction is \(1.1\) cm. If the shortest length of resonating air column with a tuning fork is \(18\) cm, the next resonating length will be
For stationary wave, \(y = 12cos(\frac{πx}{10})sin(36πt)\) cm, the distance between a node and the successive antinode is
An ideal gas (\(γ = 1.5\)) is expanded adiabatically. To reduce the root mean square velocity of molecules two times, the gas should be expanded
Assuming the expression for the pressure exerted by the gas, it can be shown that pressure is
\(15\) g of ice at \(0^{\circ}\text{C}\) is added to a vessel containing water at \(40^{\circ}\text{C}\). The mass of water and water equivalent of the vessel is \(60\) g. Assuming that negligible heat is taken from the surroundings, the final temperature of the mixture will be
[ \(L_{\text{ice}} = 80\,\text{cal/g}\) , \(S_{\text{water}} = 1\,\text{cal/g}\) ]
In most liquids, with rise in temperature surface tension of liquid
Out of the following, which statement is NOT true about black body radiation ?