Answer:
The cross sectional area in mm2 is 7.07[tex]mm^{2}[/tex]
The cross sectional area in cm2 is 0.0707[tex]cm^{2}[/tex]
Explanation:
The cross-sectional area (a) of the wire is given by;
a = [tex]\pi[/tex] x [tex]\frac{d^{2} }{4}[/tex]
where d is the diameter of the cross section = 3.00mm
1 => To find the cross-sectional area in [tex]mm^{2}[/tex], substitute the value of d = 3.00mm into the equation above as follows;
a = [tex]\pi[/tex] x [tex]\frac{3.00^{2} }{4}[/tex]
Taking [tex]\pi[/tex] to be [tex]\frac{22}{7}[/tex] we have;
a = [tex]\frac{22}{7}[/tex] x [tex]\frac{3.00^{2} }{4}[/tex]
a = 7.07[tex]mm^{2}[/tex]
2 => To find the cross-sectional area in [tex]cm^{2}[/tex], first convert the diameter in mm to cm as follows;
3.00mm = 0.3cm
Now, substitute the value of d = 0.3cm into the equation above as follows;
a = [tex]\pi[/tex] x [tex]\frac{0.3^{2} }{4}[/tex]
Taking [tex]\pi[/tex] to be [tex]\frac{22}{7}[/tex] we have;
a = [tex]\frac{22}{7}[/tex] x [tex]\frac{0.3^{2} }{4}[/tex]
a = 0.0707[tex]cm^{2}[/tex]
