BRNO UNIVERSITY OF TECHNOLOGY
Faculty of Electrical Engineering and Communication
Department of Languages
TEXTY PRO KURS LJA2
kombinovaného magisterského studia
PhDr. Marcela Borecká
BRNO UNIVERSITY OF TECHNOLOGY
Faculty of Electrical Engineering and Communication
Department of Languages
Specialized Course in Reading Skills
Earthquake detector
1) A seismograph is an instrument that locates the origin and force of earthquakes. Although
there are many different types of seismographs in use around the world, they all rely on the
same principle. One part of the instrument remains stationary, or nearly so, while another
shakes with the earth’s tremors.
2) Earthquakes generate waves that travel through the earth and cause the ground to vibrate
as they arrive at its surface. These are called seismic waves. There are four different types of
seismic waves and they all travel at different speeds.
3) To locate the origin or epicentre of an earthquake, several seismographs are placed at
different locations. By comparing the arrival times of different waves at these, the epicentre of
the earthquake can be found.
4) The electromagnetic seismograph (illustrated) consist of a coil of wire fixed to the base of
the instrument. It is arranged so that it moves in the field produced by a heavy magnet. The
magnet is known as the mass.
5)
Because of inertia, the magnet remains stationary. Inertia is the resistance of objects to
any change in their speed, even if the object is stationary. Everything has inertia and the
amount depends on its mass. The greater an object’s mass, the more inertia it has.
6) During an earthquake, the magnet remains still and the coil vibrates. As it does so, it
produces a varying electric current which is roughly proportional to the ground motion. This
signal is amplified and fed into a computer. The computer converts the current into a
fluctuating line which can be recorded on a chart.
7) Earthquakes are measured on a scale of 1 to 10 devised by Charles F. Richter in 1935.
The weaker the earthquake, the closer to zero on the scale, with each unit representing a
tenfold increase in strength.
(Adapted from The Guardian)
BRNO UNIVERSITY OF TECHNOLOGY
Faculty of Electrical Engineering and Communication
Department of Languages
BRNO UNIVERSITY OF TECHNOLOGY
Faculty of Electrical Engineering and Communication
Department of Languages
Specialized Course in Reading Skills
Earthquake detector - TASKS
A. Comprehension
a) T/F
1. Various kinds of seismographs depend on the same principle.
2. Seismic waves generated by earthquakes cause vibrations on the earth‘
surface.
3. Waves which travel through the earth‘ interior travel at a different speed
from those which travel through the earth‘s surface.
4. The source of earthquakes is identified through the use of different arrival
times of waves at one seismograph.
b) Find paragraphs which fit the following headings
1. Why the mass does not move
2. How the epicentre of an earthquake is found
3. What the parts of an electromagnetic seismograph are
4. How the seismograph works
B. Vocabulary
a) The words in italics are taken from the text. Group them in the three columns
below as follows:
______________________________________________________________________
fluctuating, locate, amplified, coil, stationary, electric current, arranged, frame, varying,
generate, amplifier, converts, seismic, mass, travel, magnetic field
________________________________________________________________
Nouns relating
to the seismograph
Verbs of physical action
Adjectives of description
BRNO UNIVERSITY OF TECHNOLOGY
Faculty of Electrical Engineering and Communication
Department of Languages
Specialized Course in Reading Skills
Earthquake detector - KEY
A. Comprehension
a) T/F
1. T
2. T
3. T
4. F
b)
1. Why the mass does not move
par. 5
2. How the epicentre of an earthquake is found
par. 3
3. What the parts of an electromagnetic seismograph are
par. 4
4. How the seismograph works
par. 6
B. Vocabulary
Nouns relating
Verbs of physical action
Adjectives of description
to the seismograph
coil
to locate
fluctuating
el.current
to arrange
stationary
frame
to generate
amplified
amplifier
to convert
varying
mass
to travel
seismic
magnetic field