Question

An iron cylinder of radius $1.4cm$and length $8cm$is found to weigh $369.6g$. Calculate the density of iron.

Answer 1

Step 1: Given data:

Length of cylinder is $l=8cm=8\times 1^{-2}m$

Radius of cylinder is $r=1.4cm=1.4\times {10}^{-2}m$

Mass of cylinder is $W=369.6g=369.6\times {10}^{-3}kg$

Let the volume of cylinder is $V$

Let the density of cylinder is $\rho$.

Step 2: Finding volume,

Volume of cylinder $=\pi r^{2}l=3.14\times {(1.4\times {10}^{-2})}^2\times 8\times {10}^{-2}=4.926\times {10}^{-5}{m}^2$

Step 3: Finding density,

$\rho =\frac{m}{V}=\frac{369.6\times {10}^{-3}}{4.926\times {10}^{-5}}=75.03\times {10}^2=7503kg{m}^3$

Hence, density of cylinder is $7503kg{m}^3$.