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alll you need is in the photo PLEASE DON' DO STEP BY STEP BECAUSE IS SO CONFUSING PUT ONLY THE ANSWER

alll you need is in the photo PLEASE DON' DO STEP BY STEP BECAUSE IS SO CONFUSING-example-1
User Mehrmoudi
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1 Answer

5 votes

The ball height is 0, when it hits the ground. So


\begin{gathered} 0=-16t^2+96t \\ -16t(t-6)=0 \end{gathered}

So from the equation, -16t = 0 or (t - 6) =0.

Evaluate the value of t for the ball hit the ground.


\begin{gathered} -16t=0 \\ t=0 \end{gathered}

OR


\begin{gathered} t-6=0 \\ t=6 \end{gathered}

The ball height is 0 at t = 0 sec and at t = 6 sec.

The t = 0 sec represent the initial condition and t = 6 sec represents the time after which ball hit the ground again.

So answer is t = 6 seconds.

PART B.

Differentiate the equation and equate to 0 for maximum height.


\begin{gathered} (d)/(dt)(h)=(d)/(dt)(-16t^2+96t) \\ (dh)/(dt)=-32t+96 \end{gathered}

For maximum height,


\begin{gathered} -32t+96=0 \\ t=-(96)/(-32) \\ t=3\text{ sec} \end{gathered}

So part B answer is 3 sec

Answer:

Part A: 6 seconds

Part B: 3 seconds