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

Answer:

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

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

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

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