Question

A mettalic pipe is 0.7cm thick.inner radius of pipe is 3.5cm and length is 5dm.find its total surface area

Answer 1

Given, thickness =0.7            Inner radius (r)=3.5            Outer radius (R)=3.5+0.7=4.2cm            Length=5 DM(50 cm)             TSA=2π(r+R)(h+R-r)              TSA=2×22÷7(3.5+4.2)(50+4.2-3.5)             TSA=44÷7×7.7×50.7=2453.8 cm sq