Homework Help: Calculus

Posted by Anonymous on Tuesday, June 15, 2010 at 10:26pm.

A fireworks shell is shot upward with an initial velocity of 28m/s from a height of 2.5 m.

s(t) = -4.9t^2 + 28t + 2.5

After how many seconds will the shell have the same speed, but be falling downward?

Calculus - Reiny, Tuesday, June 15, 2010 at 11:00pm
v(t) = -9.8t + 28

we want this to be -28 (negative for downwards)
-9.8t + 28 = -28
-9.8t = -56
t = -56/-9.8 = 5.7 seconds

Answer this Question

Related Questions

science - a shell is fired from the cannon. the shell of mass 30kg is shot with ...
calculus - A projectile is shot upward from the surface of the Earth with an ...
pyhsics - A cannonball is shot (from ground level) with an initial horizontal ...
physics - A cannonball is shot (from ground level) with an initial horizontal ...
Physics - A cannonball is shot (from ground level) with an initial horizontal ...
Physics - A cannonball is shot (from ground level) with an initial horizontal ...
Physics - A cannonball is shot (from ground level) with an initial horizontal ...
Physics - A cannonball is shot (from ground level) with an initial horizontal ...
science - a shell has an initial velocity of 450 feet per second, what is the ...
Physics - A ball is shot vertically upward from the surface of another planet. A...

For Further Reading

First Name:
School Subject:
Answer: