How Many G-Units Did Colonel John P. Stapp Experience Stopping His Rocket Sled?

[baylayA]

A world's land speed record was set by Colonel John P. Stapp when in March 1954 he rode a rocket-propelled sled that moved along a track at 1020 km/h. He and the sled were brought to a stop in 1.4 s. In g units, what acceleration did he experience while stopping?

 

[SlainTemplar]

Im pretty sure (correct me if I'm wrong) but this forum is for help on a question not the answer, what exactly are u struggling with?

 

[baylayA]

I don't know what formula to use

 

[SlainTemplar]

What are your givens and your requirements. Writing those down makes finding the correct formula to use easier

 

[baylayA]

i have km/hr of how fast he was moving and how many seconds it took for him to stop and i need to find G units of his acceleration while he was stopping.

 

[SlainTemplar]

okay so you have time, and velocity and your looking for acceleration. But Velocity can be split into V1(Initial) and V2(Final) so what was his initial velocity and final velocity?

 

[baylayA]

That is the only velocity given so I'm not sure.

 

[SlainTemplar]

Well Hes starting with a speed and he's coming to a stop.

 

[baylayA]

oh so it's original and then 0 is the final?

 

[SlainTemplar]

Thats right. so you have v1, v2, and t, and your looking for acceleration so what formula has all of those variables in it

 

[baylayA]

a= vf-vo
_____
t

thank you!

 

[baylayA]

but how do you get it into G units?

 

[SlainTemplar]

anytime, Glad i could help, don't forget to convert to g's, the conversion factor is:
1g = 9.81 m/s^2

basically 1g is the acceleration of gravity