Answer
Please see the work below.
Work Step by Step
(a) We know that
$P.E=mgh$
We plug in the known values to obtain:
$P.E=0.001\times 9.81\times 51$
$P.E=0.5J$
(b) As $K.E=\frac{1}{2}mv^2=0.5J$
We plug in the known values to obtain:
$\frac{1}{2}\times 0.001\times v^2=0.5$
$v^2=1000$
$v=32\frac{m}{s}$
(c) We know that
$q=ms\Delta T$
We plug in the known values to obtain:
$0.5J=(0.001\times 1000)\times 4.184\times \Delta T$
$\Delta T=0.12C^{\circ}$
