Question

tsa of right circular hallow cylinder

Answer 1

The total surface area of a hollow cylinder is 2π ( r1 + r2 )( r2 - r1 +h), where, r1 is inner radius, r2 is outer radius and h is height.

Answer 2

Here..

On its side of Cross section. ( hollow circular ends.)
Area = πr1²-πr2² (r1,r2-- exterior,interior cylinder radii , resp)

Since there are two sunch ends...

Are of crossection =2(πr1²-πr2²)
=2π(r1²-r2²) →

Now CSA of Exterior cylinder=2πr1h
CSA of interior Cylinder=2πr2h
So their sum =2πr1h+2πr2h
=2πh(r1+r2)

Now Adding these...

→2π(r1²-r2²)+2πh(r1+r2)
→2π[(r1²-r2²)+h(r1+r2)]
→2π[(r1-r2)(r1+r2) + h(r1+r2)]
→2π(r1+r2)[h+(r1-r2)]

So The TSA of A Hollow Cylinder=
2π(r1+r2)(h+r1-r2) ; h = height, r1= radius of bigger(exterior) circle(cylinder), r2= radius of smaller(inner) circle(cylinder).

Hope it helps...
Regards,
Leukonov.