Recall that the height of an object t seconds after it begins moving when gravity is the only force acting on the object is given. h(t)=-16x^2 + v0t + h0. h(t) is given in feet. v0 = initial velocity of object in ft/sec. ho= initial height of object in feet. If the feather is dropped from the top of the bridge 90 feet above a river, how long does it take the feather to reach the water?
That's pretty easy, have a look :
\(h(t)=−16x2=v0t+h0\)
\(v0=0 ft/sec\)
\(h0=90 ft\)
The only thing you need to do is to find t and the problem is solved.
Answer:
Time taken, t = 2.37 seconds
Explanation:
It is given that,
Height of an object at time t is given by :
\(h(t)=-16t^2+v_0t+h_0\)
Where
v₀ is initial velocity of object
h₀ is initial height of the object
The feather is dropped from the top of the bridge 90 feet above a river. we have to find the time taken by the feather to reach the water.
At the surface of water, h(t) = 0 and v₀t = 0
So, \(0=-16t^2+0+90\)
t = 2.37 seconds
The feather will take 2.37 seconds to reach the water surface.