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A Student records the initial length l, ...

A Student records the initial length l, change in temperature `DeltaT` and change in length `Deltal` of a rod as follows :

If the first observation is correct what can you say about observations 2, 3 and 4.

Text Solution

Verified by Experts

From first observation,
`alpha=(Deltal)/(lDeltaT)`
`=(4xx10^(-4))/(2xx10)`
`=2xx10^(-5)" "^(@)C^(-1)`
From second observation,
`Deltal=alphalDeltaT`
`:.Deltal=2xx10^(-5)xx1xx10`
`=2xx10^(-4)m!=4xx10^(-4)m`
`:.` Thus, the observation is incorrect
From third observation,
`Deltal=alphalDeltaT`
`=2xx10^(-5)xx2xx20`
`=8xx10^(-4)m!=2xx10^(-4)m`
`:.` Thus, the observation is incorrect.
From fourth observation,
`Deltal=alphalDeltaT`
`=2xx10^(-5)xx3xx10`
`=6xx10^(-4)m=6xx10^(-4)m`
Thus, the observation is true.
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