Question

Intensity of an earthquake is measured _______ the Richter scale. (Insert suitable preposition)

• A. in
• B. over
• C. with
• D. on

Hint:

Scales, rankings, and grading systems are generally used with the preposition “on”, such as on the Richter scale and on a scale of 1 to 10.

Answer 1

The Correct Option is D

Concept: Certain nouns related to measurement, ranking, and grading are commonly used with the preposition “on”.

Step 1: Understand what the Richter scale represents.
The Richter scale is a scientific scale used to measure the magnitude or intensity of earthquakes. Scientists compare earthquake strength according to positions on this scale.

Step 2: Recall the standard expression used with scales.
The accepted English expression is: \[ \text{measured on the Richter scale} \] Similarly, we say: \[ \text{rated on a scale of 1 to 10} \]

Step 3: Insert the appropriate preposition in the sentence.
The complete sentence becomes: \[ \text{Intensity of an earthquake is measured on the Richter scale.} \] Hence, \[ \boxed{\text{on}} \]