List of top Physics Questions

A ball of radius $ r $ and density $ \rho $ falls freely under gravity through a distance $ h $ before entering water. The velocity of the ball does not change even on entering water. If the viscosity of water is $ \eta $, the value of $ h $ is given by:
\includegraphics[width=0.5\linewidth]{28.png}

The equation of a wave on a string of linear mass density $ 0.04 $ kg/m is given by:
\[ y = 0.02 \sin 2\pi \left( \frac{t}{0.04} - \frac{x}{0.50} \right) \] The tension in the string is:

Equipotential surfaces are shown in the figure. The electric field strength will be:

A square frame of side $ 10 $ cm and a long straight wire carrying current $ 1A $ are in the plane of the paper. Starting from close to the wire, the frame moves towards the right with a constant speed of $ 10 $ m/s (see figure). The induced EMF at the time the left arm of the frame is at $ x = 10 $ cm from the wire is:

In YDSE, how many maximas can be obtained on a screen, including central maxima, on both sides of the central fringe if $ \lambda = 3000$ Å, $ d = 5000$ Å?

A force $ \mathbf{F} = \alpha \hat{i} + 3 \hat{j} + 6 \hat{k} $ is acting at a point $ \mathbf{r} = 2 \hat{i} - 6 \hat{j} - 12 \hat{k} $. The value of $ \alpha $ for which angular momentum about the origin is conserved is:

An electron (mass = $ 9 \times 10^{-31} $ kg, charge = $ 1.6 \times 10^{-19} $ C) moving with a velocity of $ 10^6 $ m/s enters a magnetic field. If it describes a circle of radius $ 0.1 $ m, then the strength of the magnetic field must be:

The force between two short bar magnets with magnetic moments $ M_1 $ and $ M_2 $ whose centers are $ r $ meters apart is 8 N when their axes are in the same line. If the separation is increased to $ 2r $, the force between them is reduced to:

A given ray of light suffers minimum deviation in an equilateral prism $ P $. Additional prisms $ Q $ and $ R $ of identical shape and of the same material as $ P $ are now added as shown in the figure. The ray will now suffer:
\includegraphics[width=0.5\linewidth]{31.png}

An $ \alpha $-particle of 10 MeV collides head-on with a copper nucleus ($ Z = 29 $) and is deflected back. The minimum distance of approach between the centers of the two is:

A car moves at a speed of $ 20 { m/s} $ on a banked track and describes an arc of a circle of radius $ 40\sqrt{3} $ m. The angle of banking is: (Take $ g = 10 { m/s}^2 $)

What will be the maximum speed of a car on a road turn of radius 30m if the coefficient of friction between the tyres and the road is 0.4? (Take $ g = 9.8 { m/s}^2 $)

A person aiming to reach the exactly opposite point on the bank of a stream is swimming with speed of $ 0.5 $ m/s at an angle of $ 120^\circ $ with the direction of flow of water. The speed of water in the stream is:

Write the principle of Wheatstone's Bridge. Find the current measured by the ammeter in the given circuit diagram.

Explain Biot-Savart law and find the unit of $ \mu_0 $ with the help of the Biot-Savart equation.

Which one of the following curves represents the variation of impedance $ (Z) $ with frequency $ f $ in a series LCR circuit?

A convex lens has power $ P $. It is cut into two halves along its principal axis. Further, one piece (out of the two halves) is cut into two halves perpendicular to the principal axis (as shown in figure). Choose the incorrect option for the reported pieces.
\includegraphics[width=0.5\linewidth]{27.png}

A Carnot engine takes $ 3 \times 10^6 $ cal of heat from a reservoir at $ 627^\circ C $, and gives it to a sink at $ 27^\circ C $. The work done by the engine is:

Assertion :
The binding energy of the nucleus increases with the increase in atomic number.
Reason :
Heavier elements have a greater number of non-radioactive isotopes than radioactive isotopes.

Two identical blocks A and B, each of mass 'm' resting on a smooth floor are connected by a light spring of natural length L and spring constant K, with the spring at its natural length. A third identical block 'C' (mass m) moving with a speed v along the line joining A and B collides with A. the maximum compression in the spring is

Light of wavelength $ \lambda_A $ and $ \lambda_B $ falls on two identical metal plates A and B respectively. The maximum kinetic energy of photoelectrons is $ K_A $ and $ K_B $ respectively. Given that $ \lambda_A = 2\lambda_B $, which one of the following relations is true?

A disc is rolling without slipping on a surface. The radius of the disc is $ R $. At $ t = 0 $, the topmost point on the disc is $ A $ as shown in the figure. When the disc completes half of its rotation, the displacement of point $ A $ from its initial position is:

Calculate the current flowing through two long parallel wires carrying equal currents and separated by a distance of 1.35 cm, experiencing a force per unit length of $ 4.76 \times 10^{-2} \, \text{N/m} $.

A solid sphere and a ring have equal masses and equal radius of gyration. If the sphere is rotating about its diameter and ring about an axis passing through and perpendicular to its plane, then the ratio of radius is $\sqrt{\frac{x}{2} }$ then find the value of x.

If the two metals $A$ and $B$ are exposed to radiation of wavelength $350 mm$. The work functions of metals $A$ and $B$ are $4.8 eV$ and $2.2 eV$. Then choose the correct option