Magnitude is a measure of the amount of energy released during an earthquake. It may be expressed using several magnitude scales. One of these, Used in Southern California, is called the Richter scale. To calculate magnitude, the amplitude of waves on a seismogram is measured, correcting for the distance between the recording instrument and the earthquake epicentre. Since magnitude is representative of the earthquake itself, there is thus only one magnitude per quake. Taking the Lawton earthquake of 1998 APR 28, as an example, one could not therefore speak of magnitude 4 at Lawton and magnitude 3 at Tulsa. The effects at the two places were different, but the magnitude of an earthquake is unique; in this example, it was 4.2 on the Richter scale. The magnitude scale is logarithmic. This means that, at the same distance, an earthquake of magnitude 6 produces vibrations with amplitudes 10 times greater than those from a magnitude 5 earthquake and 100 times greater than those from a magnitude 4 earthquake.In terms of energy, an earthquake of magnitude 6 releases about 30 times more energy than an earthquake of magnitude 5 and about 1000 times more energy than an earthquake of magnitude 4. It is very unlikely that an earthquake of magnitude less than 5 could cause any damage.

Richter Magnitude Scale
In 1935, Charles F. Richter devised a scale for quantifying the amount of energy released by an earthquake. His scale, known as the Richter scale, was a logarithmic scale based upon the relationship between an earthquake's peak amplitude, or ground motion, and the distance of the recording device from the quake's epicenter. As a base-ten logarithmic scale, each whole number increase equals a ten-fold increase in ground movement, and around 31 times the energy. The scale was designed for California earthquakes and is not reliable for magnitudes greater than seven, or distances greater than 370...

...1. 3 metres of ribbon cost £1.26.
Work out the cost of 5 metres of the same ribbon.
£ …………………………
(Total 2 marks)
2.
A Large tub of popcorn costs £3.80 and holds 200 g.
A Regular tub of popcorn costs £3.50 and holds 175 g.
Rob says that the 200 g Large tub is the better value for money.
Linda says that the 175 g Regular tub is the better value for money.
Who is correct?
………………………
Explain the reasons for your answer. You must show all your working....

...Exam Name:
AAO (Assistant Administrative Officer)
Conducted By:
LIC
Topic:
Quantitative Aptitude
1. In a division sum, the divisor is 10 times the quotient and 5 times the remainder. If the
remainder is 46, the dividend is:
(1) 4236
(2) 4306
(3) 4336
(4) 5336
2. If 1.5 x= 0.04 y, then the value of (y-x) (y+x) is:
(1) 730/77
(2) 73/77
(3) 7.3/77
(4) 703/77
3. An employee may claim Rs. 7.00 for each km when he travels by taxi and Rs. 6.00 for each
km if he drives his own car....

...Sophie
Other names
Centre Number
Candidate Number
Edexcel GCSE
Mathematics A
Paper 1 (Non-Calculator)
Foundation Tier
Thursday 28 February 2013 – Afternoon
Time: 1 hour 45 minutes
Paper Reference
1MA0/1F
You must have: Ruler graduated in centimetres and millimetres,
protractor, pair of compasses, pen, HB pencil, eraser. Tracing
paper may be used.
Total Marks
Instructions
Use black ink or ball-point pen.
Fill in the boxes at the top of this page with...

...1.37305 m/s2 .
Explanation:
Given :
θ = 13.5◦ .
Consider the free body diagram for the
block
046 10.0 points
A sample of blood is placed in a centrifuge
of radius 19.1 cm. The mass of a red blood
cell is 3.1 × 10−16 kg, and the magnitude of
the force acting on it as it settles out of the
plasma is 6 × 10−11 N.
At how many revolutions per second should
the centrifuge be operated?
Correct answer: 160.213 rev/s.
Explanation:
emmanuel (ae8272) – hw07-Waves...

...Map Scale
Chapter 2
Map Scale
You have read in Chapter 1 that the scale is an essential element of all types of maps. It is so important that if a network of lines and polygons does not carry a scale, we call it a “sketch”. Why is the scale so important ? What does it mean ? What are the different methods of showing the scale on a map? How useful is the scale in measuring the distances and the area? These are some of the questions which will be taken up in the present chapter. Glossary...

...UNIVERSITY OF CAMBRIDGE INTERNATIONAL EXAMINATIONS International General Certificate of Secondary Education
MATHEMATICS Paper 3 (Core)
*058001*
0580/03 0581/03
May/June 2006 2 hours
w w w e tr .X m eP e ap .c rs om
Candidates answer on the Question Paper. Additional Materials: Electronic calculator Geometrical instruments Mathematical tables (optional) Tracing paper (optional)
Candidate Name
Centre Number
Candidate Number
READ THESE INSTRUCTIONS FIRST Write your...

...F
Monday 9 June 2014 – Morning
GCSE MATHEMATICS A
A501/01 Unit A (Foundation Tier)
* 1 2 6 8 1 0 0 9 8 0 *
Candidates answer on the Question Paper.
Duration: 1 hour
OCR supplied materials:
None
Other materials required:
•
Scientific or graphical calculator
•
Geometrical instruments
•
Tracing paper (optional)
*
A
5
0
1
0
1
*
INSTRUCTIONS TO CANDIDATES
•
•
•
•
•
•
•
Write your name, centre number and candidate number in the boxes above. Please write
clearly and in capital...

...occupies the space equivalent to a 2 in × 2 in × 2 in cube. For a classroom with dimensions 40 ft × 40 ft × 15 ft : 40 × 40 × 15 ft 3 (12) 3 in 3 1 ball n balls = . = 518 × 10 6 ≈ 5 million balls ft 3 2 3 in 3 The estimate could vary by an order of magnitude or more, depending on the assumptions made. 2.4 4.3 light yr 365 d 24 h
1 yr 1d 3600 s 1.86 × 10 5 mi 1 h 1 s 3.2808 ft 0.0006214 mi 1 step = 7 × 1016 steps 2 ft
2.5 Distance from the earth to the moon = 238857 miles
238857...