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Waves – Doppler Effect

Explain the Doppler effect in sound and derive the formula for the observed frequency when the source is moving towards a stationary observer. Calculate the observed frequency if the source frequency is 500 Hz and the source moves towards the observer at 30 m/s. (Speed of sound = 340 m/s)

02/11/2024

Physics

12th (Science)

Thermodynamics – First Law of Thermodynamics

Explain the first law of thermodynamics and describe an isothermal process. Calculate the work done during an isothermal expansion if 2 moles of an ideal gas expand from 1 liter to 5 liters at 300 K.

02/11/2024

Physics

12th (Science)

Gravitation – Kepler’s Laws

State Kepler’s laws of planetary motion. Derive the expression for the orbital speed of a satellite around Earth using Newton’s law of gravitation.

02/11/2024

Physics

12th (Science)

Newton’s Laws – Frictional Forces

A block of mass 5 kg is placed on a horizontal surface with a coefficient of friction of 0.4. Calculate the minimum force required to move the block and the acceleration if the applied force is 50 N. (g = 9.8 m/s²)

02/11/2024

Physics

12th (Science)

Kinematics – Projectile Motion

Derive the formula for the maximum height and range of a projectile launched at an angle θ with initial velocity u. Calculate the range if u = 20 m/s and θ = 45°.

02/11/2024

Physics

12th (Science)

Electromagnetic Induction – Lenz’s Law

State Lenz’s Law. A coil is moved towards a stationary bar magnet. Explain how Lenz’s law helps determine the direction of the induced current in the coil.

02/11/2024

Physics

12th (Science)

Optics – Lens Formula and Magnification

Derive the lens formula (1/f = 1/v – 1/u) for a convex lens and explain how magnification is affected if the object distance is changed.

02/11/2024

Physics

12th (Science)

Magnetism – Force on a Moving Charge in a Magnetic Field

A proton moves at a speed of 2 x 10^6 m/s perpendicular to a magnetic field of 1 T. Calculate the force acting on the proton and its radius of the circular path. (Charge of proton = 1.6 x 10^-19 C)

02/11/2024

Physics

12th (Science)

Current Electricity – Ohm’s Law and Resistance

A wire has a resistance of 10 ohms at room temperature. Explain what happens to the resistance of the wire if (a) the wire is heated, and (b) the length of the wire is doubled while keeping its volume constant.

02/11/2024

Physics

12th (Science)

Electrostatics – Electric Field Due to a Dipole

Derive the expression for the electric field on the axial and equatorial lines of an electric dipole at a point in space.

02/11/2024

Physics

12th (Science)