ANNUAL EXAMINATION
PHYSICS
Second Year
Time Allowed: 3 Hours
Maximum Marks: 68
SECTION B
Note: Attempt any nine questions from this section. All questions carry equal marks.
Q2
i.
(36)
Describe all fundamental forces and their associated field particles
OR
Describe the structure of proton and neutron in terms of its quark composition. How
do quarks combine to form a proton and neutron.
ii.
What is half life of a radioactive element? Explain how half life of a radioactive
element can be determined mathematically.
iii.
A copper penny has a mass of 3.0 gm. Determine the energy in MeV that would be
required to break the copper nuclei into their constituent protons and neutrons. Ignore
the energy that binds the electrons to the nucleus and the energy that binds one atom
to another in the structure of the metal. Mass ₂₉Cu⁶³ = 62.939598 u.)
iv.
Find the de-Broglie wavelength of an electron in the ground state of hydrogen atom.
v.
Discuss briefly any four consequences of general theory of relativity.
OR
Explain conservation laws of pair production and annihilation of matter.
vi.
Define rectification and describe the use of diode as a half wave and full wave
rectifier.
OR
Explain the use of transistor as an amplifier or as a switch.
vii.
Construct a truth table for three input OR gate. Explain the relationship between input
and output.
Describe superconductivity and its applications.
Calculate the change in volume of a lead block of volume 1.3 m³ subjected to a
pressure of 12 atm. Also calculate the compressibility of lead. Given the bulk
modulus B = 80 × 10¹⁰ N/m².
In an RL-circuit, the resistor R is 30 Ω and the inductor L is 0.2 H. Calculate the total
impedance at a frequency of 60 Hz.
Define and explain self induction or mutual induction.
viii.
ix.
x.
xi.
xii.
xiii.
OR
Find the frequency of an A.C. generator if the voltage output is given as 200 Volt.
A moving coil galvanometer has a resistance of 50 Ω and it gives full scale deflection
at 4 mA current. A voltmeter is made using this galvanometer and a 5 kΩ resistance.
Calculate the max voltage that can be measured using this voltmeter.
Temperature difference by the surface water and bottom water in Manchester lake
might be 5°C. Assuming the surface water to be at 20°C. What highest efficiency
could a steam engine have?
OR
Calculate the change in entropy when 10 kg of water is heated from 80°C to 110°C.
Specific heat of water is 4180 J/kg·K.
OR
A balloon contains 0.04 m³ of air at a pressure of 120 kPa. Calculate the pressure
required to reduce its volume to 0.025 m³ at constant temperature.
SECTION C
Note: Attempt two questions from this section. All questions carry equal marks.
Q3
(32)
a) With the help of a graph, explain the triple point of water. Also prove mathematically
that temperature is a measure of average translational kinetic energy.
b) What is Photoelectric effect? What experimental results are obtained by hertz about
photoelectric emission? Give Einstein's explanation of photoelectric effect on the basis
of quantum theory.
Q4
a) State and explain the first law of thermodynamics. With the help of PV diagram,
explain Isobaric and Adiabatic processes.
b) Describe Thomson's experiment for the determination of e/m ratio of an electron.
OR
State Ampere law. Derive the expression for magnetic field of induction inside a long
solenoid or toroid.
Q5
a) Define sensitivity of a galvanometer? Show that the current measured by a
galvanometer is directly proportional to the deflection produced by the pointer.
OR
Write down the postulate of Bohr's atomic theory. Derive expressions for radius and
energy of nth orbit of hydrogen atom..
b) What is laser? State the principle of laser? Write its construction and derive the
working of He-Neon Laser.
OR
Explain the behavior of an RLC series circuit in terms of impedance, resonance and
phase angle.
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