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A student drops a pen from a classroom window on the third floor of the mathematics building. If the pen is dropped from33 ft above ground level, at what velocity does the pen hit the ground? Use - 32 ft/s2 for the acceleration caused by gravity.Ignore air resistance. Round any intermediate calculations to no less than six decimal places, and round your final answer totwo decimal places.

A student drops a pen from a classroom window on the third floor of the mathematics-example-1
User Barno
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1 Answer

3 votes

Answer:

45.96 m/s

Step-by-step explanation:

To find the velocity when the pen hits the ground, we will use the following equation


v^2_f=v^2_i+2ay

Where vf is the velocity when the pen hits the ground, vi is the initial velocity, a is the acceleration and y is the height of the building.

So, replacing vi = 0 m/s, a = -32 ft/s², and y = -33 ft, we get


\begin{gathered} v^2_f=0^2+2(-32)(-33) \\ v^2_f=2112 \\ vf=\sqrt[]{2112} \\ v_f=45.96\text{ m/s} \end{gathered}

Then, the pen hit the ground at 45.96 m/s

User Leventix
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