Question #8af18

1 Answer
Jul 10, 2017

18.5^oC18.5oC

Explanation:

You need the specific heat of iron in consistent units (i.e. using calories rather than joules). You can find this in the public domain, and it is 0.108 (cal)/(g.^oC)calg.oC.

Then take the relationship E = m*c*thetaE=mcθ, where E is the energy, m is the mass of substance, c is the specific heat and thetaθ is the temperature change.

Rearranging for thetaθ we have theta = E/(m*c)θ=Emc = 20/(10*0.108) = 18.5^oC20100.108=18.5oC

This, however, assumes no losses to the environment.

You can find specific heats here: www.engineeringtoolbox.com/specific-heat-metals-d_152.html

Note that they are listed in units of (kcal)/(kg.^oC)kcalkg.oC, however, these are numerically equivalent to (cal)/(g.^oC)calg.oC as 1 kcal = 1000 cal, and 1 kg = 1000 g..