Question

A hollow shaft has a cross-sectional area 125.6cm2 and a bore of 8cm in diameter. Calculate the outer diameter of the shaft to 2s.f. With the explanations please

Answer 1

The outer diameter of the shaft to 2s.f is 12.65cm

Explanation:

We know that the expression for the area of a circular cross section is

A=
`(\pi d^2)/(4)`

given data

area of cross section=
`125.6cm^2`

bore diameter d= 8cm

from the area of cross section we can solve for the outer diameter D

`Area of cross section=(\pi D^2)/(4) \\\\125.6= (3.142*D^2)/(4)`

solving for D we have

`3.142*D^2= 125.6*4\\\3.142*D^2= 502.4\\D^2= (502.4)/(3.142) \\D^2= 159.8981\\D=√(159.8981) \\D= 12.6450\\D= 12.65cm`