Wednesday

April 1, 2015

April 1, 2015

Posted by **Dan** on Tuesday, October 28, 2008 at 9:42pm.

v=2(R-r)r^2

i got the derivative:

v'=4rR-6r

what do i do next??

- Calc -
**Damon**, Tuesday, October 28, 2008 at 10:28pmI do not know the question or why you took what you call the derivative but it is not the derivative.

If

v = 2 R r^2 - 2 r^3

then

dv/dr = 4 R r - 6 r^2

However I do not understand where that equation came from.

In general the speed times the area must be constant if the density does not change much.

Therefore

Vo (pi R^2) = v (pi r^2)

v = Vo (R/r)^2

Where Vo is the speed in the open windpipe.

**Answer this Question**

**Related Questions**

Calculus Help - When a foreign object lodged in the trachea (windpipe) forces a ...

Science - What is sometime call your windpipe

Physics - The windpipe of a whooping crane is about 1.27 m long. Assuming that ...

physic - The windpipe of one typical whooping crane is 5.3 feet long. What is ...

PRE-CALC help please - A pedal socket has a radius of 4 in and the wheel socket ...

Calc - The radius of a sphere is increasing at a rate proportional to its radius...

Pre-Calc (Circles). Please help :( - Five concentric circles with radii 1, 2, 3...

calc - im so confused :( Willie Makit blows up a spherical balloon. He recalls ...

physics - A mass m is attached to a cord passing through a small hole in a ...

physics - A puck of mass 80.0 g and radius 4.10 cm slides along an air table at ...