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