UNIVERSITY OF EAST ANGLIA
School of Environmental Sciences
Main Series Undergraduate Examination 2012-2013
Candidate’s Registration No.:
FORCES OF NATURE
ENV-1A25
Time allowed: 1 hour.
Answer ALL parts of ALL questions in the spaces provided on the question
sheet.
100 marks are available for this paper.
Provided
 ENV Data Book
Hand in this paper with your answers filled in at the end of the
examination.
Notes are not permitted in this examination.
Do not turn over until you are told to do so by the Invigilator.
ENV-1A25
Copyright of the University of East Anglia
Module Contact: Dr Jenni Barclay, ENV
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1a. Give two examples of vector physical quantities.
[2 marks]
b. What are the S.I. units for mass and density ?
[2 marks]
2. Calculate the total heat energy needed to melt an iceberg of mass 6000kg
at 0oC. Is a temperature change anticipated? The latent heat of melting ice is
334 kJ/kg
[4 marks]
3. The peak mass flux during the 1980 eruption of Mt. St Helens was 2 x 107
kgs-1. Explain what this means; you may use a diagram. How does this differ
from the volume flux?
[4 marks]
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4. Explain the differences in thermal expansivity between ice, water and water
vapour.
[8 marks]
5a. Is the heat transferred from one object to another over time inversely or
directly proportional to:
(a) the conductivity of the medium
(b) the contrast in absolute temperature and
(c) the length of heating pathway?
[3 marks]
b. Which is a more efficient conductor of heat: iron or basalt?
[1 mark]
PLEASE TURN OVER
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6. Contrast elastic and ductile behaviour and give an example of each from
the Earth System.
[4 marks]
7. A ‘flubber’ glacier is moving down a drainpipe in a laboratory experiment.
Draw a plan view map of this glacier illustrating where the greatest strain is
found. Annotate your sketch to explain this distribution.
[6 marks]
8a. Following a violent storm a river experiences both unsteady and unstable
flow conditions? Explain what this means.
[2 marks]
b. Describe the motion of entrained particles in turbulent sections of the river
[2marks]
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9. What is the difference between longitudinal and transverse waves? Give an
example of each.
[4 marks]
10. The figure below shows the sea level as waves pass a fixed point.
10
water
level
(m)
8
0
10
20
30
40
50
60
70
80
Time (s)
6
From the figure, deduce values for the amplitude of the wave and the period
of the wave.
[4 marks]
11. What is the pressure at a depth of 2000 m in the ocean if the mean
density of the water is 1028 kg m-3 and acceleration due to gravity is
9.8 m s-2?
[4 marks]
PLEASE TURN OVER
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12. What makes a hot air balloon ascend or descend?
[2 marks]
13. If seawater has a density of 1028 kg m-3, what is the mass of 5 m3 of
seawater?
[4 marks]
14. How much energy would a 60 W light bulb use in 4 minutes?
[4 marks]
15. State two things that the amount of power generated by a wind turbine
depends on.
[4 marks]
16. Explain what is meant by steric sea level rise.
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[4 marks]
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17. What vertical forces act upon an iceberg floating in water?
[4 marks]
18. A person has a mass of 60 kg. Calculate their weight on Earth and in
space.
[4 marks]
19. What is the pressure beneath a column of fluid of density 1.2 kg m -3 and
height 2000 m?
[4 marks]
20. State four types of radiation in the electromagnetic spectrum.
[4 marks]
21. What is the difference between black body and grey body radiation?
[4 marks]
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22. How does a greenhouse keep the plants inside warm?
[4 marks]
23. What happens to a wave when it enters a region with a different wave
speed?
[4 marks]
24. What is a tsunami?
[4 marks]
END OF PAPER
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