If a construction worker drops a wrench from the top of a building 450 feet high

We know that the rate of change of the position of a given object is equal to the velocity of that object.

We will find that the velocity of the wrench after 2 seconds is -64ft/s

Now we know that the height (vertical position) of the wrench is:

s(t) = -16*t^2 + 450

Then to get the velocity equation we need to differentiate this, remember the general rule:

Then we will get that the velocity equation is:

v(t) = 2*(-16)*t + 0

v(t) = -32*t

And because the position is in ft, this velocity will be in ft per second.

Then the velocity of the wrench 2 seconds after it was dropped is given by:

v(2) = -32*2 = -64

Then the velocity of the wrench after 2 seconds is -64ft/s

If you want to learn more, you can read:

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-64ft/s

Explanation:

Given:

Unknown:

For t = 2:

1 watt = 1 joule/second

1 KW = 1,000 joule/second

Work = (power) x (time)

3.6 x 10⁴ J = (2,984 joules/second) x (time)

time = (3.6 x 10⁴J) / (2,984 J/s)

time = (36,000J) / (2,984 J/s)

time = 12.06 seconds