Physics-
General
Easy
Question
A rod of length 1000 mm and co-efficient of linear expansion 
per degree is placed symmetrically between fixed walls separated by 1001 mm. The Young's modulus of the rod is 
. If the temperature is increased by 
, then the stress developed in therod is (in 
):
- 10
- cannot be calculated
The correct answer is:
The change in length of rod due to increase in temperature in absence of walls is
But the rod can expand upto 1001 mm only. At that temperature its natural length is = 1002 mm.
\ compression = 1mm
\ mechanical stress =
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