Question

Sara has a fire in the fireplace to warm her 20°C apartment. She realizes that she has left the iron poker in the fire. How hot is the fire if the 0.60 m poker lengthens 0.30 cm? (αiron = 12 x 10-6°C-1)

Answer 1

You can use the expression for linear expansion as:
`Deltal=l_0alphaDeltaT`
Where `l_0` is the initial/original length, `alpha` is the linear expansion coefficient and `DeltaT` is the variation of temperature.
So you get:
`0.3=60*12xx10^-6*(T_(fire)-20)`
So: `T_(fire)=437°C`