E$16$ Unit $091-$ Assessment $5\mathrm{.}0.$docx

$Aa$

Expansion is calculated using the formula: $e=1000x$

LxaxT

$e=$ expansion in metres

$L=$ length of free$*$ rail $(m),*$ note "free rail" means unclipped and unrestricted to move lengthwise

$a=$ coefficient of linear expansion $=0\mathrm{.}0000115$

$T=$ difference between actual temperature and $27C$ i$.$e$.-$ rail temperature$)$

Extension $(e)=$ Length of rail in metres $(L)x$ coefficient of linear expansion $($a$)x$ difference between actual temperature and $27C(T)$

Q$1)$ Calculate extension of $175$ metres of rail at $22C$

:$e=1000L$axT

$E=10001750\mathrm{.}0000115(27C-22C)$

$E=10001750\mathrm{.}00001155$

$E=10\mathrm{.}06mm$

Q$2)$ Calculate extension of $225$ metres of rail at $16C$