Respuesta :
The answer for this is actually b. 79 m/s
I submitted it to odyssey-ware and i got the question correct
Answer:
B. 79 m/s
Explanation:
Since we have information about the distance of the fall, we can use the following formula to find the final velocity of the object:
[tex]v_{f}^2=v_{i}^2+2gh[/tex]
clearing for [tex]v_{f}[/tex]
[tex]v_{f}=\sqrt{v_{i}^2+2gh}[/tex]
where [tex]v_ {f}[/tex] is the final velocity (when it hits the ground), [tex]v_ {i}[/tex] the initial velocity, [tex]g[/tex] is the acceleration of gravity ([tex]g=9.8m/s^2[/tex]), and [tex]h[/tex] is the height from where the rock is dropped, in this case: [tex]h=320m[/tex]
Assuming that the rock was only dropped without adding an initial velocity, [tex]v_ {i}[/tex] is zero.
Substituting all the values in the formula:
[tex]v_{f}=\sqrt{(0)^2+2(9.8m/s^2)(320m)}[/tex]
[tex]v_{f}=\sqrt{6272}[/tex]
[tex]v_{f}=79.2m/s[/tex]
The value that best approximates from the options is 79 m/s, the answer is B.
