If a construction worker drops a wrench

from the top of a building 375 feet high the

wrench will be

s (t) = - 16t2 + 375

feet above the ground after t seconds.

Determine the velocity of the wrench 4 seonds after it was was dropped.

Answer in units of ft/sec

... ?

To find velocity at a given moment, also known as instantaneous velocity, we need to know how to take the derivative of an equation;

you can take the derivative of s (t) = 62t^2 + 375 by first moving the 2 in front of 162 and multiply both which well give you 324t and 375 will turn to 0

-16t^2 results in - 32t

so our velocity at t=4 is - 32 (4) = - 128ft per second