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Explore Class 12 Physics past and model questions by chapter, year, marks and question type.
478 questions found
Prove that bright and dark fringes are equally spaced in Young's double slit experiment.
Why do we prefer a wrench of longer arm over a wrench of shorter arm?
A parallel beam of monochromatic light is incident on a diffraction grating having 500 lines/mm to get second order maxima at 30°. Calculate the wavelength of light used.
State and prove Brewster's law.
Define laminar flow and turbulent flow of liquid.
Explain the variation of thermoelectric emf with the temperature of the hot junction of a thermocouple.
What happens in an adiabatic process?
Volume remains constant
Pressure remains constant
Temperature remains constant
The system is insulated from the surroundings
The efficiency of Carnot engine operating between steam point and ice point is
26.8%
50%
73.2%
100%
Which of the following is an example of transverse wave?
Sound wave in air
Waves inside the water
Wave produced in the stem of vibrating tuning fork
Wave produced in the stretched string
Which one of the following phenomena is not explained by Huygen's construction of wave front?
Refraction
Reflection
Polarization
Diffraction
The magnetic field intensity at the center of a circular coil of radius R and carrying current I is
μ₀I/R
μ₀I/2R
μ₀I/2πR
2μ₀I/R
If χ is the magnetic susceptibility of a material then its relative permeability (μᵣ) is
χ + 1
χ − 1
1/χ
1 + χ²
What is the point where the seismic waves start called?
Epicenter
Metacenter
Hypocenter
Seismic center
An oil drop of mass 3 × 10⁻¹¹ g and of radius 2 × 10⁻⁶ cm carries 10 excess electrons. Its terminal velocity when:
i) falling in a region in which there is no electric field. [1]
ii) falling in an electric field of 3 × 10⁵ V m⁻¹ directed downward? [1]
(Viscosity of air = 1.8 × 10⁻⁵ Nsm⁻²)
Obtain an expression for velocity of an electron in nth orbit of hydrogen atom.
For an oscillating object, the displacement versus time curve shown in figure. What is the velocity of the object in the mean position?
0.2π m/s
0.4π m/s
2π m/s
4π m/s
A train is approaching a cliff at 10 m/s. The driver sounds a whistle of frequency 600 Hz. What will be the frequency of echo as heard by the driver?
(Velocity of sound in air = 340 m/s)
If the galvanometer and battery are interchanged at the balance position, how will the balance point get affected?
The product of moment of inertia and angular velocity gives
force
torque
linear momentum
angular momentum
The bob of a simple pendulum has a mass of . The pendulum oscillates with a period of and an amplitude of . At an extreme point in its cycle, it has a potential energy of . What is the kinetic energy of the pendulum bob at its mean point?
$0.022\ \text{J}$
$0.044\ \text{J}$
$0.011\ \text{J}$