Question

Stapp rode a rocket sled, accelerating from rest to a top speed of 282 m/s (1015 km/h) in 5.00 s, and was brought jarringly back to rest in only 1.40 s! Calculate his (a) acceleration and (b) deceleration. Express each in multiples of g (9.80 m/s2) by taking its ratio to the acceleration of gravity.

Answer 1

a)
`a=5.74\ g\ m/s^2`

b)
`a=20.55\ g\ m/s^2`

Step-by-step explanation:

Given that

Initial velocity u =0 m/s

Speed at 5 s v= 282 m/s

Rocket accelerated up to 5 s :

We know that

v= u + at

282= 0+ a x 5

`a=56.4\ m/s^2`

So the acceleration

`a=56.4\ m/s^2`

`a=5.74\ g\ m/s^2`

Rocket come to rest in 1.4 s :

Final velocity of rocket v=0 m/s

Initial velocity = 282 m/s

v= u + at

0= 282 - a x 1.4

`a=201.42\ m/s^2`

`a=20.55\ g\ m/s^2`

So the deceleration

`a=20.55\ g\ m/s^2`