Explanation:
thermal expansion ∝L = (δL/δT)÷L ----(1)
δL = L∝L + δT ----(2)
we have δL = 12.5x10⁻⁶
length l = 200mm
δT = 115°c - 15°c = 100°c
putting these values into equation 1, we have
δL = 200*12.5X10⁻⁶x100
= 0.25 MM
L₂ = L + δ L
= 200 + 0.25
L₂ = 200.25mm
12.5X10⁻⁶ *115-15 * 20
= 0.025
20 +0.025
D₂ = 20.025
as this rod undergoes free expansion at 115°c, the stress on this rod would be = 0
Correct answer is option E. No dimensions
As we know formula Pressure (P) is
also,
- Dimensional formula of <em>Pressure is </em>

- Dimensional formula of <em>length is L </em>
- Dimensional formula of <em>mass is M</em>
- Dimensional formula of <em>velocity is </em>

So, as given W=
Dimensional formula of W =
since all terms get cancelled
Work is dimensionless i.e no dimensions
Learn more about dimensions here brainly.com/question/20351712
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