List of top Physics Questions

If in Young's double slit experiment, fifth bright fringe is located at a distance of 0.3 mm from the central bright fringe, then the distance of the seventh dark fringe from the central bright fringe is:
If the formation of a real image using a biconvex lens of material of refractive index 1.5 is shown in the figure. If this setup is immersed in water (refractive index = $\frac{4}{3}$), then
formation of a real image using
If the third harmonic of a closed pipe is in resonance with the fourth harmonic of an open pipe, then the ratio of the lengths of the closed and open pipes is:
The heat to be supplied to 20 g of oxygen to increase its temperature from 27 $^\circ$C to 59 $^\circ$C at constant pressure is (Universal gas constant = 8.3 J mol$^{-1}$ K$^{-1}$)
500 g of water at a temperature of 73 °C is mixed with 45 g of steam at a temperature of 100 °C. The ratio of the initial mass of steam and the mass of steam at equilibrium of the mixture is
Four moles of a diatomic gas at a temperature of 927 $^\circ$C expands adiabatically such that its volume increases by 3100%. The work done by the gas is (Universal gas constant = 8.3 J mol$^{-1}$ K$^{-1}$)
If the coefficient of performance of a refrigerator is 5 and the temperature inside it is -20 °C, then the temperature of its surroundings is
If four moles of hydrogen and two moles of helium form a gaseous mixture, then the molar specific heat capacity of the mixture at constant pressure is
If the equation representing the relation between displacement 'x' and velocity 'v' of a particle executing simple harmonic motion is $4v^2 = 25 - x^2$, then the time period of the particle is (All the quantities in the equation are in SI units)
If two rain drops of radii $r_1$ and $r_2$ reach the ground with terminal velocities $v_1$ and $v_2$ and linear momenta $p$ and $32p$ respectively, then $r_1 : r_2 =$
The length of the scale of a spring balance that can weigh zero to 100 kg is 25 cm. If a body suspended from this balance oscillates with a time period of $0.2\pi$ s, then the mass of the suspended body is (Acceleration due to gravity = $10 \text{ m s}^{-2}$)
If a body of mass 'm' is projected at an angle '$\theta$' with the horizontal with an initial velocity 'u', then the average torque on the body during the flight is (g - acceleration due to gravity)
A satellite is launched into a circular orbit of radius R around the earth. A second satellite is launched into another circular orbit of radius 1.01 R around the earth. The period of revolution of the second satellite is larger than that of the first one by a percent of (approximately)
A swimmer who can swim in still water at a speed of 20 kmph wants to cross a river flowing at speed of 10 kmph along shortest path, then the angle with the direction of flow in which he has to swim is
The minimum force required to stop a body of mass 4 kg moving along a straight line with a velocity of 54 kmph in a distance of 9 m is
A simple pendulum of length 1m is released from horizontal position. If 20% its initial energy is lost due to air resistance in reaching the mean position, then the speed of the bob of the pendulum at mean position is (Acceleration due to gravity = 10 m s\textsuperscript{-2})
A block of mass 2 kg is kept on a rough horizontal surface. If a horizontal force of 4 N is applied on the block, then the acceleration of the block is (Coefficient of static friction between the block and the surface is 0.3)
The work done to take a body of mass 100 kg to the top of a building of height 20 m is (Acceleration due to gravity = 10 m s\textsuperscript{-2})
A solid sphere of mass 2 kg and radius 10 cm is rolling down on an inclined plane without slipping. If the rotational kinetic energy of the sphere is 40 J, then its total kinetic energy is
If the speed of projection of a projectile is twice its speed when it is at maximum height, then the angle of projection is
A body moving along a straight line path travels first 10 m distance in a time of 3 seconds and the next 10 m distance with a velocity of 5 m s\textsuperscript{-1}. The average velocity of the body is
If \(\sigma\) denotes Stefan constant and S denotes heat capacity, then the dimensional formula of \(\frac{\text{S}}{\sigma}\) is
If a bullet of mass 2 g travels with velocity of 3 × 103 cm s-1, its wavelength (in m) is: (h = 6.6 × 10-34 Js)

In the given circuit, the input voltage across base resistance 10V. If base-emitter and collector-emitter voltages are zero, then the current amplification factor of the transistor is:

If the junction diodes $D_1$ and $D_2$ in the given circuit are ideal, then the forward biased resistance and reverse biased resistance is infinity: