List of top Physics Questions

If the values of the temperature of a body in Fahrenheit and Celsius scales are in the ratio of 13 : 5, then the temperature of the body is
In a hydraulic lift, if the radius of the smaller piston is \(5 \ \text{cm}\), and the radius of the larger piston is \(50 \ \text{cm}\), then the weight that the larger piston can support when a force of \(250 \ \text{N}\) is applied to the smaller piston is
The force required to stretch a steel wire of area of cross-section \(1 \ \text{mm}^2\) to double its length is
(Young’s modulus of steel \(= 2 \times 10^{11} \ \text{N/m}^2\))
When the mass attached to a spring is increased from 4 kg to 9 kg, the time period of oscillation increases by \(0.2\pi\) s. Then the spring constant of the spring is
For a particle executing simple harmonic motion, the ratio of kinetic and potential energies at a point where displacement is one half of the amplitude is
Three thin uniform rods each of mass \( M \) and length \( L \) are placed along the three axes of a Cartesian coordinate system with one end of all the rods at origin. The moment of inertia of the system of the rods about z-axis is
A thin uniform circular disc rolls with a constant velocity without slipping on a horizontal surface. Its total kinetic energy is
A body is projected at an angle of \(60^\circ\) with the horizontal. If the initial kinetic energy of the body is \(X\), then its kinetic energy at the highest point is
A body is moving along a straight line under the influence of a constant power source. If the relation between the displacement (s) of the body and time (t) is \(s \propto t^x\), then \(x =\)
Two balls each of mass 250 g moving in opposite directions each with a speed 16 m/s collide and rebound with the same speeds. The impulse imparted to one ball due to the other is
A train of mass \(10^6 \, \text{kg}\) is moving at a constant speed of \(108 \, \text{km/h}\). If the frictional force acting on it is \(0.5 \, \text{N per 100 kg}\), then the power of the train is
A particle crossing the origin at time \(t = 0\), moves in the xy-plane with a constant acceleration ‘a’ in y-direction. If the equation of motion of the particle is \(y = bx^2\) (where \(b\) is a constant), then its velocity component in the x-direction is
The magnitudes of two vectors are A and B (A>B). If the maximum resultant magnitude of the two vectors is ‘n’ times their minimum resultant magnitude, then \(\frac{A}{B} =\)
The ratio of the displacements of a freely falling body during second and fifth seconds of its motion is
The dimensional formula of Planck’s constant is
An unpolarised beam of light incidents on a group of three polarising sheets arranged such that the angle between the axes of any two adjacent sheets is $30^\circ$. The ratio of the intensities of polarised light emerging from the second and third sheets is
Two solid spheres each of radius \( R \) made of same material are placed in contact with each other. If the gravitational force acting between them is \( F \), then
An AC power supply of 220 V at 50 Hz, a resistor of 20\( \Omega \), a capacitor of reactance 25\( \Omega \) and an inductor of reactance 45\( \Omega \) are connected in series. The corresponding current in the circuit and the phase angle between the current and the voltage is, respectively :
The wavelength of spectral line corresponding to electron transition \( n = 3 \) to \( n = 2 \) for \( \text{Li}^{2+} \) ion is \( \lambda \,\text{nm} \). What is the wavelength (in nm) corresponding to electron transition \( n = 4 \) to \( n = 1 \) for \( \text{He}^+ \) ion?
The minimum length of an antenna to transmit a signal of frequency \( 3 \text{ kHz} \) is
If the angular momenta of electrons in two orbits of hydrogen atom are \( \frac{h}{\pi} \) and \( \frac{1.5h}{\pi} \), then the ratio of velocities of electrons in these two orbits is
(h – Planck’s constant)
If two diodes \( D_1 \) and \( D_2 \) are connected as shown in the figure, then
If two diodes
If the collector and base currents of a transistor in common emitter configuration are 5 mA and 50 \(\mu\)A, then the current amplification factor of the transistor is
If the half-life of a radioactive substance is 32 hours, then the fraction of the substance decayed in 4 days is
If a capacitor of 500 nF is connected to an AC source of frequency 1 kHz, then the capacitive reactance of the capacitor is