How Long Does It Take for Captain Kirk to Fall to the Valley Floor?

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The discussion revolves around calculating the time it takes for Captain Kirk to fall to the valley floor from a height of 59 meters. The participant has used the formula d=1/2gt^2 and calculated a fall time of 3.645 seconds, which does not match any of the provided answer choices. They also calculated Kirk's potential energy as 63,602 J and his kinetic energy after falling for 2.7 seconds as approximately 9,626.81 J. Additionally, there is confusion about using average velocity versus instantaneous velocity when determining Kirk's speed after 2.7 seconds of free fall. The conversation highlights the importance of understanding the physics concepts involved in free fall and energy calculations.
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How long would it take...

Homework Statement


This is a problem that followed a bunch of others so I will post what I got for those as well.

Here is the problem: How long would it take Kirk to fall to the valley floor?

5.29s or 3.47s or 11.836s or 2.43s or none of those. I am not getting any of them, I don't know if I am doing it correct. I am using the d=1/2gt^2 formula and get 3.645s. Distance being 35.721m and g being 9.8.

And that number is not any of the choices listed... is it non of the above?

Homework Equations



Captain James T Kirk is on vacation in Ca. He is climbing 59m above the floor of the valley when he stops to rest. Cpt. Kirk has a mass of 110kg. What is the potential energy of Kirk? I got 63602J, using the PE=mgh formula.
His kinetic energy would be 0 when he rests.

Kirk suddenly looses his grip and begins to fall! How far does he fall in 2.7s? I got 35.721m using d=1/2gt^2

What is Kirks velocity after falling for 2.7s? I got 13.23m/s using the v=d/t formula.

What is his kinetic energy after falling for 2.7s? I am not sure about that one, but I got 9626.8095J using the kinetic formula KE=1/2mv^2

What is his potential energy after falling 2.7s? Using the potential energy formula P subscript E =mgh I came up with 38507.238J.

Thank you for your time.
 
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I should also say that the number I got for what his kinetic energy after falling for 2.7s is not listed either. I just do not have anyone to compare my work with currently.
 


Justhelp said:

Homework Statement


This is a problem that followed a bunch of others so I will post what I got for those as well.

Here is the problem: How long would it take Kirk to fall to the valley floor?

5.29s or 3.47s or 11.836s or 2.43s or none of those. I am not getting any of them, I don't know if I am doing it correct. I am using the d=1/2gt^2 formula and get 3.645s. Distance being 35.721m and g being 9.8.

And that number is not any of the choices listed... is it non of the above?

Homework Equations



Captain James T Kirk is on vacation in Ca. He is climbing 59m above the floor of the valley when he stops to rest. Cpt. Kirk has a mass of 110kg. What is the potential energy of Kirk? I got 63602J, using the PE=mgh formula.
His kinetic energy would be 0 when he rests.

Kirk suddenly looses his grip and begins to fall! How far does he fall in 2.7s? I got 35.721m using d=1/2gt^2

What is Kirks velocity after falling for 2.7s? I got 13.23m/s using the v=d/t formula.

What is his kinetic energy after falling for 2.7s? I am not sure about that one, but I got 9626.8095J using the kinetic formula KE=1/2mv^2

What is his potential energy after falling 2.7s? Using the potential energy formula P subscript E =mgh I came up with 38507.238J.

Thank you for your time.

How far does he fall if he falls all the way to the valley floor.

BTW: (The correct answer is) there.)
 


Using d=rt?
 


But..I don't have time.
 


I can't use distance or time because the numbers I got were for 2.7s.
 


Justhelp said:

Homework Statement


This is a problem that followed a bunch of others so I will post what I got for those as well.

Here is the problem: How long would it take Kirk to fall to the valley floor?

5.29s or 3.47s or 11.836s or 2.43s or none of those. I am not getting any of them, I don't know if I am doing it correct. I am using the d=1/2gt^2 formula and get 3.645s. Distance being 35.721m and g being 9.8.

And that number is not any of the choices listed... is it non of the above?

Homework Equations



Captain James T Kirk is on vacation in Ca. He is climbing 59m above the floor of the valley when he stops to rest. Cpt. Kirk has a mass of 110kg. What is the potential energy of Kirk? I got 63602J, using the PE=mgh formula.
His kinetic energy would be 0 when he rests.

Kirk suddenly looses his grip and begins to fall! How far does he fall in 2.7s? I got 35.721m using d=1/2gt^2

What is Kirks velocity after falling for 2.7s? I got 13.23m/s using the v=d/t formula.

What is his kinetic energy after falling for 2.7s? I am not sure about that one, but I got 9626.8095J using the kinetic formula KE=1/2mv^2

What is his potential energy after falling 2.7s? Using the potential energy formula P subscript E =mgh I came up with 38507.238J.

Thank you for your time.


His velocity after falling 2.7 sec is not d/t, because his velocity has been changing as he accelerates downward. d/t is his average velocity after 2.7 sec, not his instantaneous velocity. You know his acceleration and his initial velocity (zero), so, again, what is his velocity after 2.7 sec?
 


Justhelp said:
...

Captain James T Kirk is on vacation in Ca. He is climbing 59m above the floor of the valley...

How far does he fall if he falls all the way to the valley floor?
 
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