The velocities of sound waves in four media P,Q,R and S are `18,000 km//h, 900 km//h, 0km//h`, and 1200 km/h respectively. Which medium could be a liquid substance?

Options

A. P
B. Q
C. R
D. S

Answer

To determine which medium among P, Q, R, and S could be a liquid substance based on the velocities of sound waves provided, we can analyze the given velocities:

1. **Identify the velocities of sound in the media:**
- Medium P: 18,000 km/h
- Medium Q: 900 km/h
- Medium R: 0 km/h
- Medium S: 1,200 km/h

2. **Understand the properties of sound in different states of matter:**
- Sound travels fastest in solids, slower in liquids, and slowest in gases.
- The general order of sound velocity is: Solid > Liquid > Gas.

3. **Analyze the given velocities:**
- The highest velocity is in medium P (18,000 km/h), which indicates it is likely a solid.
- Medium Q has a velocity of 900 km/h, which is relatively slow and suggests it could be a liquid.
- Medium R has a velocity of 0 km/h, which indicates that sound cannot travel through this medium (it could be a vacuum).
- Medium S has a velocity of 1,200 km/h, which is faster than medium Q but slower than medium P, suggesting it could be a gas.

4. **Conclusion:**
- Based on the analysis, medium Q (900 km/h) is the only medium that fits the characteristics of a liquid substance, as it has a velocity that is slower than that of solids but faster than that of gases.

**Final Answer:** Medium Q could be a liquid substance.

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