600 - (-16t^2 + 1000
5 - t
= (16*t^2- 400)/(5-t)
= 16(t^2-25)/(5-t)
= 16(t-5)(t+5)/(5-t)
= -16(t+5)
lim -16(t+5) =-160
t->5
This is the velocity hence the negative sign indicating it is moving down
the speed is 160
Use the position function s(t) = -16t^2 + 1000, which gives the height in feet of an object that has fallen for t seconds from a height of 1000 feet. the velocity at time t = a seconds is given by:
lim s(a) - s(t)
t to a a - t
if a construction worker drops a wrench from a height of 1000 feet, how fast will the wrench be falling after 5 seconds?
the answer is 160ft/sec
but i am not sure how to get there,
this is what i have so far:
-16 * 5^2 +1000 = 600
600 - (-16t^2 + 1000)
5 - t
where do i go from here? please help!