Posted by **Amber** on Tuesday, April 24, 2012 at 12:05am.

A flower pot is dropped from a point 12 feet above the ground,so that it will land 4 feet from the base of a 12 foot lamppost. At what rate is the shodow of the flower pot moving along the ground when the pot is 8 feet above the ground?

- Calculus -
**Steve**, Tuesday, April 24, 2012 at 12:24am
height y = 12 - 16t^2

shadow at x, similar triangles, so

x/12 = (x-4)/y

or,

xy = 12x - 48

y dx/dt + x dy/dt = 12 dx/dt

y=8 when t=1/2

x=6 when y=8

(12 - 16t^2) dx/dt + x (-32t) = 12 dx/dt

at t=1/2,

8 dx/dt - 96 = 12 dx/dt

dx/dt = 96/-4 = -24 ft/s

- Calculus - PS -
**Steve**, Tuesday, April 24, 2012 at 4:50am
Oops.

x=12 when y=8

make the change and percolate it through the rest of the solution.

## Answer this Question

## Related Questions

- Calculus - A man standing 9 feet from the base of a lamppost casts a shadow 6 ...
- Math - function problems - 1) A box with a square base has a total surface area ...
- physics gr 12 - A flower pot is dropped from the balconey of an apartment 28.5 ...
- Math Urgent help please - A lamppost casts a shadow of a man who is standing 15 ...
- 7th grade Ms. Sue help Pygorean Theoream asap quic - 3. A ladder is leaning ...
- Pre Cal - a 6 foot person is standing x feet away form a 10 foot lamppost. What ...
- General Physics - A 6 kg flower pot falls from a window ledge 10 meters above ...
- physic - As you look out of your dorm window, a flower pot suddenly falls past. ...
- physic - As you look out of your dorm window, a flower pot suddenly falls past. ...
- calculus - A tight rope is stretched 30 feet above the ground between the Jay ...