Question

Rocket-powered sleds are been used to test the
responses of humans to acceleration. Start-
ing from rest, one sled can reach a speed of
530 m/s in 1.58 s and can be brought to a stop
again in 2.7 s.
Find the acceleration of the sled while ac-
celerating.
Answer in units of m/s2

Find the acceleration of the sled when brak-
ing.
Answer in units of m/s2

Answer 1

acceleration = change in speed / time

Answer 2

speed of 530 m/s in 1.58 s = change in speed is 530m/s

can be brought to a stop again in 2.7 s. = change in speed is -530m/s (from 530 m/s to zero m/s)

Answer 3

Yes it is that way.
\[a=\frac{v_f-v_0}{\Delta t}\]
In the first case, v0=0 m/s, vf=530 m/s, Δt=1.58 s. In the second, vf=0 m/s, v0=530 m/s, Δt=2.7 s

Answer 4

hmm so it's just 335.443 m/s^2 and 196.296m/s^2

Answer 5

the 196.296 answer is wrong... do you know why?

Answer 6

Oh wait is it negative?

Answer 7

Yes! Because you doesn't put the - sign.

Answer 8

The value must be negative.

Answer 9

;)

Answer 10

whoops forgot that was important ._. thanks

Answer 11

You're welcome.

Answer 12

335.443 m/s^2

damn, that's like 33+ g's, for 1.5 seconds