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75 POINTS!!!

3. A model rocket is launched from the ground with an initial velocity of 352 ft/sec. e. How long will it take the rocket to reach its maximum height? Show all work in the space provided. f. Assume the model rocket’s parachute failed to deploy and the rocket fell back to the ground. How long would it take the rocket to return to Earth from the time it was launched? Show all work in the space provided.

Respuesta :

At max height (the so-called apex of trajectory) the vertical velocity is equal to zero ; since V = Vo-g*t = 0 , then Vo = g*t and t = Vo/g = 352/32 = 11.0 sec 

h = 0 = Vo*t-g/2*t^2 
16t^2 = Vo*t 
t cross 
t = Vo/16 = 352/16 = 22.0 sec....which is twice the time needed for getting the apex

Hello!

The model rocket takes 11 sec going up, and takes 11 sec coming down, in total it takes total 22 seconds to reach it's maximum height to it's lowest point ( which is the ground) .

I hope it helps!