Ok I did it.
Here is my working:
4\pir2 = 200
r2 = 200/4\pi
r = Square root of 50/\pi
dS/dr = 8\pir
= 8\piSquare root of 50/\pi
= 100.27 cm2/cm
Thanks everyone for all your help :smile:
Unfortunately I won't be able to view the video as it will take a while to download and I've got to get going to school for an excursion. Thank you though.
So if I try:
200*4pi
= 2513.27
Get the square root of that makes 50.1325
Multiple by 2 for some reason? Makes 100.265. Rounded off...
Homework Statement
I am 99% positive I did a) correctly, as the answer is correct according to the answer in the back of my textbook. However, I cannot do b).
The question: A spherical balloon is being inflated. Find the rate of change of the surface area with respect to the radius when...