List of top Physics Questions

The power of an engine which draws 1000 kg of water from a well of depth 9 m in one minute is (acceleration due to gravity $g = 10$ m/s$^2$)
The force, $F = (2x^2 + 5x + 4)$ N is acting on a body. If the body moves from $x = -1$ m to $x = +1$ m in the direction of force, then the work done by the force is
In a Young’s double slit experiment, a laser light of wavelength 560 nm produces an interference pattern with consecutive bright fringes’ separation of 7.2 mm. Now another light is used to produce an interference pattern with consecutive bright fringes’ separation of 8.1 mm. The wavelength of the second light is:
A message signal of frequency 14 kHz is used to modulate a carrier of frequency 900 kHz. Then, the frequencies of the sidebands are:
The photo current in a photo diode depends on:
Electromagnetic waves of energy flux $ 75 \times 10^4 \, \text{W/m}^2 $ incidents normally on a surface of area $ 40 \, \text{cm}^2 $. If the surface absorbs the flux completely, the total momentum delivered to the surface in one second is: Options:
The process that mainly takes place in stars to produce energy:
The minimum excitation energy of an electron revolving in the first orbit of hydrogen is:

In the circuit, $ E_1 = E_2 = E_3 = 2 \, \text{V} $ and $ R_1 = R_2 = 4 \, \Omega $. Then the current flowing through $ E_2 $ is:

Switch $ S $ is closed. Now the switch is opened and the free space between the plates of the capacitors is filled with a dielectric of dielectric constant 3. The ratio of total electrostatic energy stored in the capacitors before and after the introduction of the dielectric is:

The resultant resistance between $ A $ and $ B $ in the given figure is:

The change in internal energy when 20 g of a gas is heated from $ 25^\circ C $ to $ 35^\circ C $ at constant volume is: Options:
The gravitational potential energy of a system of three masses $ m $, $ 2m $, and $ 3m $ placed at the three vertices of an equilateral triangle of side $ a $ is Options:
The temperature of the earth without the greenhouse effect will be: Options:
A ball is dropped from some height and after first collision with the ground if it reaches $ \frac{3}{4} $th of its original height, then the % loss of its energy is: Options:
A solid sphere and a solid cylinder roll down without slipping along an inclined plane. If they start from rest from the top of the inclined plane, the ratio of the velocities of the solid sphere and solid cylinder when they reach the bottom of the inclined plane is:
A pendulum of time period one second is losing its mechanical energy due to damping. Its mechanical energy at time $ t = 0 $ is 45 J. After completing 15 oscillations, its mechanical energy is 15 J. The ratio of the damping constant and the mass of the object making damped oscillations is:
The potential difference across the ends of a conductor is $ (50 \pm 3) $ V and the current through it is $ (5 \pm 0.1) $ A. The percentage error in the measurement of the resistance of the conductor is: Options:
The time taken by a boat to travel upstream to a certain distance and return back is 14 hours. If the velocity of boat in still water is 35 kmh$ ^{-1} $ and velocity of the stream is 5 kmh$ ^{-1} $, the distance travelled by the boat before it returns is
A capacitor and a resistor are connected in series to an ac source of variable frequency. When the frequency of the ac source becomes $ \frac{1}{3} $rd of its initial value, the current in the circuit decreases by 50%. The power factor of the circuit at the initial frequency is
A radioactive element A with half life 3 hours decays to a stable element B. After a time $ t $, the ratio of A and B atoms is 1:16 then the time $ t $ in hours is
If the electric field of an electromagnetic wave is increased by 100%, then the energy density of the wave increases by
The force between two spheres with charges +7 $ \mu C $ and -5 $ \mu C $ is F. If each sphere is given an additional charge of +2 $ \mu C $, the new force of attraction will be
A liquid of density $ 3000 \, \text{kg/m}^3 $ and coefficient of viscosity $ 0.1 \, \text{Pas} $ flows through a pipe with diameter $ 0.05 \, \text{m} $ with a velocity of $ 0.2 \, \text{m/s} $. The Reynolds number of the fluid is
At atmospheric pressure, 1 g of water has a volume of 1671 cm³ in vapor phase. The change in internal energy when 1 g of water changes from liquid to vapor phase at atmospheric pressure is