The correct option is (c) 1 and 3 only.
Explanation
The Richter scale is a quantitative measure used to define the magnitude of an earthquake. It quantifies the energy released during an earthquake based on the amplitude of seismic waves recorded by seismographs.
Statement-wise Analysis
- Statement 1 is Correct. The Richter scale is designed to measure the magnitude of an earthquake. Magnitude is a measure of the energy released at the source of the earthquake, as opposed to intensity, which measures the strength of shaking produced by the earthquake at a certain location.
- Statement 2 is Incorrect. The Richter scale is logarithmic, not linear. Because of the logarithmic basis, each whole number increase in magnitude represents a tenfold increase in measured amplitude. In terms of energy, each whole number increase corresponds to the release of approximately 31.6 times more energy. Therefore, an increase of 2 on the scale represents an energy release increase of approximately 1,000 times ($31.6 \times 31.6$), not double.
- Statement 3 is Correct. The scale was developed in 1935 by American seismologists Charles F. Richter and Beno Gutenberg at the California Institute of Technology.
Key Takeaway: The Richter scale measures earthquake magnitude and is logarithmic in nature. A magnitude increase of 1 corresponds to a 10-fold increase in wave amplitude and approximately a 32-fold increase in energy release.