Question

Fill in the blanks:
Most destructive earthquakes have magnitudes __________ on the Richter scale.
A. 4
B. 7
C. Less than 7
D. Higher than 7.

Answer 1

Hint: A Richter scale has no limits. Hence the largest value among the given options forms the most destructive magnitude of earthquakes on the Richter scale.

Complete step by step answer:
The Richter scale was developed by Charles F. Richter to measure the strength of earthquakes. The Richter scale is a logarithmic scale. Each number on the scale denotes an amplitude ten times greater than the number preceding it. For example, the amplitude of a level 5 earthquake is 10 times greater than a level 4 earthquake and an earthquake of level 6 has an amplitude 100 times greater than level 4 earthquake. Earthquakes which measure 3 on the Richter scale are very light and mostly not felt. A very small portion of the total earthquakes measure above 7 on the scale. These earthquakes are majorly destructive. The largest reading on the Richter scale that has been registered till date is 9.5. It struck in Chile in 1960.

So, the correct answer is “Option D”.

Note:
The Richter scale only gives us a reading. An approximate impact can be estimated from these readings. But the impact of an earthquake on an area depends not only on its magnitude but also the type of ground, strength and positions of the man-made structures in that area etc. The extent of damage by an earthquake is accurately given by the Mercalli scale. The earthquakes are rated on the Mercalli scale depending upon the extent of damage it creates.