MCQ
The mechanical equivalent of heat:
- AHas the same dimension as heat.
- BHas the same dimension as work.
- CHas the same dimension as energy.
- ✓Is dimensionless.
✓
Answer
Correct option: D.
Is dimensionless.
Explanation:
If the mechanical work done (W) produces the same temperature change as heat (H), then the mechanical equivalent of heat (J) is equal to $\frac{\text{W}}{\text{H}}.$ Thus,
$\text{J}=\frac{\text{W}}{\text{H}}$
Since the unit of work and heat is the same, mechanical equivalent of heat is dimensionless.
If the mechanical work done (W) produces the same temperature change as heat (H), then the mechanical equivalent of heat (J) is equal to $\frac{\text{W}}{\text{H}}.$ Thus,
$\text{J}=\frac{\text{W}}{\text{H}}$
Since the unit of work and heat is the same, mechanical equivalent of heat is dimensionless.
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