JEE MainPhysicsHeat and ThermodynamicsMCQ+4 / −1
For a given gas at 1 atm pressure, rms speed of the molecule is 200 m/s at 127°C. At 2 atm pressure and at 227°C, the rms speed of the molecules will be :
- A100 m/s
- B100 m/s
- C80 m/s
- D80 m/s
View written solutionFree
Correct answer: B
- Use the formula for rms speed
For an ideal gas, So for a given gas, since and are constant,
This means rms speed depends only on absolute temperature, not on pressure.
- Convert temperatures to Kelvin
Initial temperature:
Final temperature:
- Relate the two rms speeds
Given:
Using we get
- Match with options
corresponds to Option B.
- Comparison with stored answer
Stored correct answer: B
Our derived answer: B
So they agree.
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