Question

A concrete column has a diameter of 390 mm and a length of 2.8 m . If the density (mass/volume) of concrete is 2.45 Mg/m3, determine the weight of the column in pounds.

Answer 1

Answer:  1804.61 lbs

Explanation:

Given, diameter of concrete column = 390 mm

= 0.390 m  [ 1 mm =0.001 m]

⇒ Radius = $\dfrac{0.390}{2}=0.195\ m$

also, Length = 2.8 m

Volume of column  (cylindrical)= $\pi r^2l$

$=(3.14)(0.195)^2(2.8)$

$=0.3343158\ m^3$

Density  $=\dfrac{Mass }{Volume}=2.45\ Mg/m^3$  

⇒ Mass = 2.45 x (Volume)

= 2.45 (0.3343158) Mg

= 0.81907371 Mg

⇒ Mass = 819.07271 kg  [1 Mg =1000 kg]

Weight = ${mass}\times{gravity}={819.07271}\times{9.8}=8026.91\ N$

1 N= 0.22482 lb

Then, Weight = $0.22482\times 8026.91=1804.61\ lb$

Weight of the column in pounds.= 1804.61 lbs (approx)

Answer 2

Weight of the column is 1804.61 lbs.

Given that,

• Diameter of column is 390mm or 0.39m.
• Length (l) of column is 2.8m.
• Density of column is 2.45 Mg/m3

According to the given data, calculation are as follows,

Diameter = 0.39m

So, radius (r) = 0.39 $\div$ 2 = 0.195m

Volume of column = $\pi r^{2}l$

By putting the value, we get

Volume = [ (3.14)$\times$ $(0.195)^{2}$ $\times$ 2.8m ]

= $0.3343158m^{3}$

Now, as we know that,

Density = Mass $\div$ Volume

Or, Mass (M) = Density $\times$ Volume

= 2.45 $\times$ 0.3343158

= 819.07271 kg

Now Weight = (M $\times$ Gravity )         Value of gravity is 9.8.

Weight = 819.07271 kg $\times$ 9.8

= 8026.91N

Where, 1N = 0.22482 lbs

So, Weight of the column = 1804.61 lbs

Learn more : https://brainly.com/question/21667661