(a)What is the difference between Divergence, Gradient, and Curl. Give one example of each. [10]
(b)A particle moves in the xy plane, starting from the origin at t= 0 with an initial velocity having an x component of 20 m/s and a y component of -15 m/s. The particle experiences an acceleration in the x direction, given by a x = 4 m/s². Determine the total velocity vector at any time. [10]
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Q. 3
(a)What is law of conservation of angular momentum? Give at least one example. [8]
(b)A 6 kg block initially at rest is pulled to the right along a horizontal surface by a constant horizontal force of 12N. Find the speed of the block after it has moved 3m if the surfaces in contact have a coefficient of kinetic friction of 0.15. [10]
(c)Can a normal force do work? If not, why not? If so, give an example. [2]
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Q. 4
(a)What is Kepler's third law? Prove that the square of the period is proportional to the cube of the semimajor axis. [12]
(b)Consider a satellite of mass m moving in a circular orbit around the Earth at a constant speed v and at an altitude h above the Earth's surface. Determine the speed of satellite in terms of G (Universal Gravitational Constant), h, R (the radius of the Earth), and M (the mass of the Earth). [8]
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Q. 5
(a)What is Bernoulli's Theorem? Show that P+½ρν²+ρgh = constant [10]
(b)Where P is pressure of the fluid, ρ is density of the fluid, v is velocity of the fluid, g is acceleration due to gravity, and h is height above a reference level. In a car lift used in a service station, compressed air exerts a force on a small piston that has a circular cross section of radius 5 cm. This pressure is transmitted by a liquid to a piston that has a radius of 15 cm. What force must the compressed air exert to lift a car weighing 1000 N? [10]
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Q. 6
(a)What is Young's double-slit experiment? Derive the mathematical formula for constructive and destructive interference of light. [12]
(b)A 200g block connected to a light spring for which the force constant is 5 N/m is free to oscillate on a frictionless, horizontal surface. The block is displaced 5cm from equilibrium and released from rest. Find the period of its motion. [8]
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Q. 7
(a)What is diffraction of light? Explain diffraction of X-rays by crystals. [10]
(b)Monochromatic light from a helium–neon laser (λ = 632 nm) is incident normally on a diffraction grating containing 4000 grooves per centimeter. Find the angles at which the second-order maximum is observed. [10]
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Q. 8
(a)What is first-law of thermodynamics? Show that work done on the gas during isothermal expansion of an ideal gas is W = nRT ln (Vf/Vi) where R is universal gas constant, T is temperature, n is number of moles. Vi and Vf is the initial and final volume, respectively. [12]
(b)A 1 mole sample of an ideal gas is kept at 0°C during an expansion from 3 L to 10 L. How much work is done on the gas during the expansion? [8]
The 2026 CSS Physics paper set by the Federal Public Service Commission. Question wording only; questions marked “Not yet checked” have not been compared with the official paper yet. Open the official paper beside the questions to check any of them.
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