List of top Physics Questions

In Young’s double-slit experiment using monochromatic light of wavelength \(λ\), the intensity of light at a point on the screen where path difference is \(λ\), is k units. What is the intensity of light at a point where path difference is \(\frac{λ }{3}\)?
A dip circle is taken to geomagnetic equator. The needle is allowed to move in a vertical plane perpendicular to the magnetic meridian. The needle will stay
Two bars ot copper having same length but unequal diameter are heated to the same temperature. The change in length will be
What is the force between two small charged spheres having charges of \(2 × 10^{−7} C \) and \(3 × 10^{−7} C \) placed 30 cm apart in air?
A slit of width a is illuminated by red light of wavelength $ 6500\, \overset{\text{o}}{\mathop{\text{A}}}\, $ . If the first minimum falls at $ \theta =30{}^\circ , $ the value of $ a $ is
The time period of rotation of the earth around its axis so that the at the objects at the equator become weightless is nearly $(g=9.8m/s^2)$,Radius of earth =6400 km.
Three bricks each of length $L$ and mass $M$ are arranged as shown from the wall. The distance of the centre of mass of the system from the wall is
The moment of inertia of a thin uniform rod of mass M and length L about an axis passing through its midpoint and perpendicular to its length is $I_0$. Its moment of inertia about an axis passing through one of its ends and perpendicular to its length is
A body is initially at rest. It undergoes one-dimensional motion with constant acceleration. The power delivered to it at time t is proportional to
A projectile has
Feeling of weightlessness in a satellite or spaceship is due to
Two lead balls of masses m and 5m having radii R and 2R are separated by 12R, If they attract.each other by gravitational force, the distance covered by small sphere before they touch each other is
A 3.0 cm wire carrying a current of 10 A is placed inside a solenoid perpendicular to its axis. The magnetic field inside the solenoid is given to be 0.27 T. What is the magnetic force on the wire?
Equal volumes of monoatomic and diatomic gases at the same temperature are given equal quantities of heat. Then
The displacement of a body is given to be proportional to the cube of time elapsed. The magnitude of the acceleration of the body, is
A conducting loop is placed in a uniform magnetic field with its plane perpendicular to the field. An emf is induced in the loop if
A beam of light consisting of two wavelengths, 650 nm and 520 nm, is used to obtain interference fringes in a Young’s double-slit experiment.
(a) Find the distance of the third bright fringe on the screen from the central maximum for wavelength 650 nm.
(b) What is the least distance from the central maximum where the bright fringes due to both the wavelengths coincide?
In a Young’s double-slit experiment, the slits are separated by 0.28 mm and the screen is placed 1.4 m away. The distance between the central bright fringe and the fourth bright fringe is measured to be 1.2 cm. Determine the wavelength of light used in the experiment.

𝑆1 and 𝑆2 are two identical sound sources of frequency 656 Hz. The source 𝑆1 is located at 𝑂 and 𝑆2 moves anti-clockwise with a uniform speed of 4\(\sqrt{2}\) ms-1 on a circular path around 𝑂, as shown in the figure. There are three points 𝑃, 𝑄 and 𝑅 on this path such that 𝑃 and 𝑅 are diametrically opposite while 𝑄 is equidistant from them. A sound detector is placed at point 𝑃. The source 𝑆1 can move along the direction 𝑂𝑃. [Given: The speed of sound in air is 324 ms-1]. When only 𝑆2 is emitting sound and it is at 𝑄, the frequency of sound measured by the detector in Hz is _________

Which of the following is NOT the reason for calling steel more elastic than rubber ?
The momentum of an electron revolving in \(n ^{\text {th }}\) orbit is given by : (Symbols have their usual meanings)
If X times momentum is work, then the dimensiona! formula of X Is
A car is moving with a uniform speed of 72 km/h. After applying brakes it stops after traveling 100 m distance. If its mass along with the passengers is 1000 kg, then the value of force due to the application of brakes will be in newton:
The photoelectric cut-off voltage in a certain experiment is 1.5 V. What is the maximum kinetic energy of photoelectrons emitted?
The work function of caesium metal is \(2.14 eV\). When light of frequency \(6×1014Hz\) is incident on the metal surface,photoemission of electrons occurs. What is the
(a)maximum kinetic energy of the emitted electrons, 
(b)Stopping potential, and
(c)maximum speed of the emitted photoelectrons?