Question

For water, coefficient of cubical expansion after $4{}^{o}C$ is ${\gamma }_1$ and before $4{}^{o}C$ is ${\gamma }_2$ then

• A. ${\gamma }_1=0and{\gamma }_2=positive$
• B. ${\gamma }_1=negativeand{\gamma }_2=positive$
• C. ${\gamma }_1=0and{\gamma }_2=negative$
• D. ${\gamma }_1=positiveand{\gamma }_2=negative$

Answer 1

The correct option is D ${\gamma }_1=positiveand{\gamma }_2=negative$

Before $4{}^{o}C$ water contracts on heating, hence ${\gamma }_2=-veandat4{}^{o}C$, $\gamma$ changes sign from $-$ve to $+$ve as water expands on heating, hence ${\gamma }_1$ is positive.