LOYOLA COLLEGE (AUTONOMOUS), CHENNAI – 600 034
|
B.Sc. DEGREE EXAMINATION –PHYSICS
FIFTH SEMESTER – APRIL 2007
PH 5400 – GEO PHYSICS
Date & Time: 30/04/2007 / 1:00 – 4:00 Dept. No. Max. : 100 Marks
PART – A 10×2=20 marks
Answer ALL questions.
- How can one seismically distinguish between an earth quake and a large explosion?
- What is the implication of a shadow zone in the internal structure of the earth?
- Distinguish between Rayleigh and Love seismic surface waves.
- Give the significant differences between the body wave and the surface wave.
- Define the term focus and epicentre.
- Write down the Laplace’s and Poisson’s equation obeyed by the gravitational potential.
- Explain briefly the Gauss method of determining the earth’s magnetic field.
- Write a note on geological time scale.
- List the two possible sources of heat with in the earth.
- How are the ages of rocks determined?
PART – B
Answer any FOUR questions. 4×7.5=30 marks
- What are P and S waves? Describe the method by which the epicentre of an earthquake is located.
- Outline the principle and construction of the strain seismograph.
- Write a brief account of the magnitude and occurance of earthquakes.
- Explain the dynamo theory of Earth’s magnetism with the help of the Faraday disc generator.
- Discuss the variation of temperature with in the earth.
PART-C Answer any FOUR questions. 4×12.5=50 marks
- Discuss the analogy between an optic wave and a seismic wave interms of reflection and refraction phenomenon.
- Discuss the theory of horizontal seismograph with a neat diagram and explain all possible cases.
- Explain the working of a) Hammond and Faller method of measuring gravity and b) Worden gravity meter with neat diagram.
- Explain the theory of a) saturation magnetometer and b) Alkali vapour magnetometer.
- Given the theory of radioactive dating of rocks and minerals using a) the decay scheme of Rb87 and b)the decay scheme of K40.____________________
Latest Govt Job & Exam Updates: