(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

i am trying to apprixmate the surface area of a hemisphere.

i am approximating by cutting the sphere into cylinders of different radius, and using their curved surface area to approximate.

each cylinder will have a height of r.cos.theta and radius of r.sin.theta.

so the surface area should be =

integral [pi/2 to 0] (2.pi * r.sin.theta * r.cos.theta * d.theta)??

but that gives me -pi r^2 which is wrong...

anyidea where i went wrong?

**Physics Forums | Science Articles, Homework Help, Discussion**

Dismiss Notice

Join Physics Forums Today!

The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

# Homework Help: Approximating surface area of hemisphere

**Physics Forums | Science Articles, Homework Help, Discussion**