Question

an iron pillar of a cylindrical portion of 2.8 m height and 20 cm in diameter and a cone of 42 cm height surrounding it. find the weight of pillar of 1 cubic cm of iron weighs 7. 5 g

Answer 1

Hey!!

Here is your answer...

As it says... which is cylindrical in shape and height,radius is given.

We will have time find the weight.

1 cubic centemeter weighs 7.6 kg.

We will have to find the volume first,

The formula for the volume of the cylinder is

Pie * radius * radius * height.

Pie take it 22/17 (3.14).. I will take it as 3.14

20 cm in diameter...

Then, 10 in radius.

Height is 2.8 m

=> 280 cm.

Volume = 280*3.14*10*10

=> 280*314

=> 87920 cubic centemeter.

Now, for the cone which is surrounding the cylinder

The formula for the volume of a cone is

Pie * radius * radius * height / 3

Radius is 10 , it will be same as this structure is surrounding the cylindrical structure..

And height is 42 cm.

Volume will be =

3.14 * 10 * 10 * 42/3

=> 314 * 42 / 3

=> 13188 / 3

4396 cubic centimeter.

Now, the total volume is 4396+87920

= 92316 cubic centimeter.

@ 1 cubic centimeter is 7.6 kg..

92316 cubic centimeter will be

=> 92316 * 7.6

=> 701601 kg

Hope this helps..