List of top Physics Questions

A resistor of resistance $ 10\, \Omega $ is connected across a $ 20\, V $ battery. Calculate the current flowing through the resistor.
The rate constant $ k $ of a reaction doubles when the temperature is raised from 300 K to 310 K. Calculate the activation energy $ E_a $ of the reaction. (Use $ R = 8.314 \, J/mol\cdot K $)
An object is placed $ 30\, cm $ in front of a convex lens of focal length $ 20\, cm $. Find the position of the image.
A particle is projected vertically upward with an initial velocity of $ 20 \, m/s $. Calculate the maximum height reached by the particle.
How much heat is required to raise the temperature of $ 2 \, kg $ of water from $ 20^\circ C $ to $ 80^\circ C $? (Specific heat capacity of water = $ 4200 \, J/kg^\circ C $)
Two charges of +3 μC and –3 μC are placed 2 cm apart in air. What is the electric potential energy of the system? (Take \( k = 9 \times 10^9 \) Nm\(^2\)/C\(^2\))
A body of mass 2 kg is moving with a velocity of 5 m/s. How much work is required to stop the body?
A particle starts from rest and accelerates uniformly at 4 m/s\(^2\). What is the distance covered in the 5th second?
A current of 3 A flows through a resistor of resistance 4 Ω for 2 minutes. The heat produced is:
Three resistors of $ 2\, \Omega $, $ 3\, \Omega $, and $ 6\, \Omega $ are connected in parallel. What is the equivalent resistance of the combination?
If a force of $ 10 \, \text{N} $ displaces a body by $ 5 \, \text{m} $ in the direction of the force, the work done is:
A block of mass $ 5\, \text{kg} $ is placed on a rough horizontal surface. A horizontal force of $ 25\, \text{N} $ is applied. If the coefficient of friction is $ 0.4 $, what is the acceleration of the block? (Take $ g = 10\, \text{m/s}^2 $)
Water flows through a horizontal pipe with a velocity of 2 m/s. The cross-sectional area of the pipe reduces to half. What is the velocity of water in the narrower section?
The wavelength of a photon is 500 nm. Calculate its energy. (Planck’s constant \( h = 6.63 \times 10^{-34} \, \text{J·s} \), speed of light \( c = 3 \times 10^8 \, \text{m/s} \))
A wire of length 0.5 m carrying a current of 3 A is placed in a magnetic field of 2 T perpendicular to the wire. What is the force on the wire?
A light wave of wavelength 600 nm passes from air into a medium with refractive index 1.5. What is the wavelength of light in the medium?
A solid sphere of mass 2 kg and radius 0.5 m rolls without slipping down an inclined plane of height 3 m. What is its speed at the bottom? (Take \( g = 9.8\, \text{m/s}^2 \))
An ideal gas expands from 2 L to 6 L at a constant temperature of 300 K. Calculate the work done by the gas if pressure remains constant at 2 atm. (1 atm = $1.013 \times 10^5$ Pa)
How much heat is required to raise the temperature of \( 2 \, \text{kg} \) of water from \( 25^\circ C \) to \( 75^\circ C \)? (Specific heat capacity of water \( c = 4200 \, \text{J/kg}^\circ C \))
A 3 m long wire of radius 3 mm shows an extension of 0.1 mm when loaded vertically by a mass of 50 kg in an experiment to determine Young's modulus. The value of Young's modulus of the wire as per this experiment is $ P \times 10^{11} \, \text{N/m}^2 $, where the value of $ P $ is: (Take $ g = 3\pi \, \text{m/s}^2 $)
Two metal spheres of radius $ R $ and $ 3R $ have same surface charge density $ \sigma $. If they are brought in contact and then separated, the surface charge density on smaller and bigger sphere becomes $ \sigma_1 $ and $ \sigma_2 $, respectively. The ratio $ \frac{\sigma_1}{\sigma_2} $ is:
Two balls with the same mass and initial velocity are projected at different angles in such a way that the maximum height reached by the first ball is 8 times higher than that of the second ball. $ T_1 $ and $ T_2 $ are the total flying times of the first and second ball, respectively, then the ratio of $ T_1 $ and $ T_2 $ is:


Space between the plates of a parallel plate capacitor of plate area 4 cm$^2$ and separation of $ d = 1.77 \, \text{mm} $, is filled with uniform dielectric materials with dielectric constants (3 and 5) as shown in figure. Another capacitor of capacitance 7.5 pF is connected in parallel with it. The effective capacitance of this combination is ____ pF.

An electron is released from rest near an infinite non-conducting sheet of uniform charge density '–σ'. The rate of change of de-Broglie wavelength associated with the electron varies inversely as $n^{th}$ power of time. The numerical value of $n$ is ______.
A sample of a liquid is kept at 1 atm. It is compressed to 5 atm which leads to change of volume of 0.8 cm$^3$. If the bulk modulus of the liquid is 2 GPa, the initial volume of the liquid was ______ litre. (Take 1 atm = $10^5$ Pa)