Answer:
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×[tex]r^2[/tex]×h = (22÷7)×
V1=V
or,0.9h=(22÷7)×[tex]r^{2}[/tex]×h
or,0.29 = [tex]r^{2}[/tex]
:.r = 0.54cm
So, diameter of rod = 2r = 2×0.54 = 1.08cm