Assume that the heat lost from the iron goes into just melting the ice and does not raise its temperature
Q (lost) = Q (gained)
mcDT (iron) = mLf (ice)
0.1 x 460 x (150 - 0) = m x 3.34 x 105
6900 = m x 3.34 x 105
m = 0.0206 kg (= 20.6 g)
Density (D) = m/V
Density of ice at 0oC is 0.9162 g/cm3
V = m/D = 20.6/0.9162 = 22.48 cm3
Length of cylinder = Volume/Area = 22.48/(p r2)
L = 22.48/(p x 22) = 1.79 cm (the answer in back of the book says 1.9 cm and this is wrong).
My thanks to Oscar Lee from St Joseph's College, Gregory Terrace, Brisbane for pointing out the error.
I'd normally send him a packet of Tim Tams but as they are made with palm oil I've stopped buying them. Sorry Oscar.
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