Question

2. A hang glider dropped his cell phone from a height of 450 feet. How many seconds did it take the cell phone to reach the ground?3. An accident investigator measured the skid marks of one of the vehicles involved in an accident. The length of the skid marks was 84 feet. What was the speed of the vehicle before the brakes were applied?4. How far from the base of the house do you need to place a 13-foot ladder so that it exactly reaches the top of a 10-foot tall wall?5. A baseball diamond is a square that is 90 feet on each side. What is the distance a catcher has to throw the ball from home to second base?

Answer 1

Explanation:

2.

In order to calculate how many seconds it took, we can use the free fall formula:

\Delta S=\frac{gt^2}{2}ΔS=

2

gt

2

Where DeltaS is the displacement, g is gravity and t is the amount of time.

So, using DeltaS = 450 and g = 9.81, we have:

\begin{gathered}\begin{gathered} 450=\frac{9.81\cdot t^2}{2} \\ 9.81t^2=900 \\ t^2=\frac{900}{9.81} \\ t^2=91.74312 \\ t=9.578\text{ s} \end{gathered}\end{gathered}

450=

2

9.81⋅t

2

9.81t

2

=900

t

2

=

9.81

900

t

2

=91.74312

t=9.578 s

So it took 9.578 seconds for the cellphone to reach the ground.

Answer 2

2.

In order to calculate how many seconds it took, we can use the free fall formula:

`\Delta S=(gt^2)/(2)`

Where DeltaS is the displacement, g is gravity and t is the amount of time.

So, using DeltaS = 450 and g = 9.81, we have:

`\begin{gathered} 450=(9.81\cdot t^2)/(2) \\ 9.81t^2=900 \\ t^2=(900)/(9.81) \\ t^2=91.74312 \\ t=9.578\text{ s} \end{gathered}`

So it took 9.578 seconds for the cellphone to reach the ground.