First slide
Thermal expansion
Question

The variation of length of a substance along three principal directions with temperature is shown in the figure. The average superficial expansivity of the substance is

Moderate
Solution

{\alpha _x} = \frac{{2004.0 - 2000.0}}{{2000.0 \times (10 - 0)}} = 2 \times {10^{ - 4}}/^\circ C

{\alpha _y} = \frac{{2003.2 - 2000.0}}{{2000.0 \times (10 - 0)}} = 1.6 \times {10^{ - 4}}/^\circ C

{\alpha _z} = \frac{{2000.8 - 2000.0}}{{2000.0 \times 10}} = 0.4 \times {10^{ - 4}}/^\circ C

\alpha = \frac{{{\alpha _x} + {\alpha _y} + {\alpha _z}}}{3} = \frac{{(2 + 1.6 + 0.4) \times {{10}^{ - 4}}}}{3}

= \frac{4}{3} \times {10^{ - 4}}/^\circ C

\beta = 2\alpha = 26.67 \times {10^{ - 5}}/^\circ C

Get Instant Solutions
When in doubt download our app. Now available Google Play Store- Doubts App
Download Now
Doubts App