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|01-09-2011, 10:58 AM||#1|
CSS Physics Paper 2011-2012
CSS Exam Physics Paper 2011-2012
Q.2 a) define a scalr field,obtain an expression for the Gradient of a scalar field. Why the gradient of a scalar field is vector?
b) Given phi (x,y,z) = X2yz3 (x square y z cube)
find grad at phi (1,2,1)
c) for what values of 'a' ,the vector A = 2i+aj+k and B= 4i -2j-2k are perpendicular.
Q.3 a) Distinguish between Linear and Angular momentum. Explain the law of conservation of angular momentum. Prove that the Angular momentum is constant in the absence of external torque.
b) The angular momentum J ps a particle is given as kj = 8 t powers 4 i- 2 t square j + 12 t cube k. find the torque at t=1
Q.4 a) Discuss in detail the relativity of mass, time and length.
b) What is time dilation? Explain with example.
c) When we say that a clock in moving frame runs slower than a clock in a stationary frame. What does it mean?
Q.5 a) Differentiate between streamline and turbulent motion of a liquid.
b)What is" coefficient of viscosity"? Explain in detail the Stoke's Law applicable in determining the coefficient of viscosity of a viscous liquid experimentally.
c) Why do auto manufactures recommend using different viscosities of engine oil in cold and hot climate,
Q.6 a) what is polarization of light? Explain Polarization by reflection and obtain Brewstar Law. Also explain the idea of double reflection.
b) We wish to use a Quartz sheet (n=1.54) in air as polarizer. Find the polarizing angle and angle of refraction.
Q.7 a) Define internal energy. State and explain First and Third laws of thermodynamics.
b) what is heat engine ?Determine the efficiency of the engine if it takes 10,000 J of heat and delivers 2000 J of work per cycle.
Q.8 write note on any TWO:
i) centre of mass
ii) diffraction grating and Resolving Power
iii)Production of low temperature.
|01-09-2011, 10:59 AM||#2|
Re: CSS Physics Paper 2011-2012
Physics Paper 2010
Q.2 a) State and prove Gauss's law in electrostatics and express the law in differential forms.
b) Find the electricity intensity at a point outside a volume distribution of charge confined into a spherical region of radius R.
Q.3 a) State and explain Ampere's law . Derive an expression for the value of 'B' inside a solenoid.
b) a thin 10 cms long solenoid has a total of 400 turns of wire and carries a current of .20 ampere. Calculate the field inside near the centre.(given μ0 = 12.57 *10 powers-7 T-m/A )
Q.4 a How a semi conductor diode is used as a half wave and full wave rectifier?
b) What are the transistors? Give construction and symbol of PNP and NPN transistor.
c) The resistivity of a metal increases with increase in temperature while that of a semi conductor decreases. Explain
Q.5Discuss briefly the wave number of matter and obtain an expression of de Broglie's wavelength for matter waves.
b) calculate de Broglie's wavelength of a .20 kg ball moving with a speed of 15m/s.
Q.6 a) Derive Einstein's photoelectric effect on the basis of quantum theory and derive Einstein's Photoelectric equations.
b) calculate the work function of NA in electron volts given that the threshold wavelength is 6800. 6.625 * 10-34 J-S
Q.7 a)Define the terms decay constant ,half life and average life as applied to a radioactive substance. Find the relation between them.
b)The half life of radium is 1590 years . In how many years will one gm of pure element
i) lose one centigram
ii) be reduced to one centigram
c) Whena nucleus emitsa gamma ray photon ,what happens to its atomic number and its actual mass.
Q.8 Write notes on any Two:
a) self and mutual inductance
b) Pauli's Exclsusion Principle
c) Compton Scattering