# the chain rule

A 16-ft ladder leans against a wall. The bottom of the ladder is 5 ft from

the wall at time t = 0 and slides away from the wall at a rate of 3 ft/s.

Find the velocity of the top of the ladder at time t = 1.

a) The textbook response to this question is - sqrt (3) is approximately equal too

-1.732 ft/s. The minus sign

means the top of the ladder is sliding down. Check that the textbook's answer is

correct.

b) The speed of sound at sea level using the standard atmosphere is about 340.29

meters per second. There are 3.280840 feet in one meter. Using the assumptions

of this model, find the angle between the ladder and the ground at the time that

the top of the ladder breaks the speed of sound.

c) The speed of light is about 299,792,458 meters per second. There are still

3.280840 feet in one meter. Using the assumptions of this model, find the an-

gle between the ladder and the ground at the time that the top of the ladder moves

at the speed of light.

https://brainmass.com/math/calculus-and-analysis/the-chain-rule-387356

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Pythagoras theorem is also reiterated in order to solve.