An object dropped from a height of 600 feet has a height, h(t), in feet after t seconds have elapsed, such that h(t) = 600 − 16t 2 . Express t as a function of height h, and find the time to reach a height of 400 feet.

Respuesta :

given h = 600 - 16t ( add 16t to both sides )

16t + h = 600 ( subtract h from both sides )

16t = 600 - h ( divide both sides by 16 )

t = [tex]\frac{600-h}{16}[/tex]

when h = 400

t = [tex]\frac{600-400}{16}[/tex] = [tex]\frac{200}{16}[/tex] = 12.5 seconds


Answer:

The required time is 3.54 seconds approximately or [tex]\frac{5}{2}\sqrt{2}[/tex] seconds.

Step-by-step explanation:

Consider the provided function.

[tex]h(t) = 600-16t^2[/tex]

Where t represents the time in seconds and h represents the height.

It is given that we need to find the time to reach a height of 400 feet.

Substitute h(t)=400 in the above function.

[tex]400= 600-16t^2[/tex]

[tex]400- 600=-16t^2[/tex]

[tex]-200=-16t^2[/tex]

[tex]200=16t^2[/tex]

[tex]\frac{50}{4}=t^2[/tex]

[tex]t=\sqrt{\frac{50}{4}} \\t=\frac{5}{2}\sqrt{2}[/tex]

Neglect the negative value as time should be a positive number.

Or

[tex]t\approx 3.54[/tex]

Hence, the required time is 3.54 seconds approximately.