An iron pipe of internal diameter 2.8cm and Uniform thickness 1mm is melted and a solid same length is formed. find the diameter of the rod . cylindrical rod of the rod

The correct answer is : 1.08cm

Explanation:

Given : Internal diameter = 2.8cm

Radius = 1.4cm

Thickness = 1mm = 0.1cm

External radius = 1.4cm + 0.1cm = 1.5cm

Solution:

(V1) volume of hollow pipe = pie×h×(R+r)(R-r) = (22÷7 )×h×2.9×0.1 = 0.9hcm²

(V) volume of rod with same length = pie××h = (22÷7)×

V1=V

or,0.9h=(22÷7)××h

or,0.29 =

:.r = 0.54cm

So, diameter of rod = 2r = 2×0.54 = 1.08cm