Answer:
a) W = - 3387525.12 J = - 3.39 MJ
b) F = - 19031.04 N = - 19 KN
Explanation:
First, we need to find the deceleration of the rocket by using the third equation of motion:
[tex]2as = v_{f}^2 - v_{i}^2\\[/tex]
where,
a = deceleration = ?
s = distance covered = 178 m
vf = final speed = 0 m/s
vi = 284 m/s
Therefore,
[tex]2a(178\ m) = (0\ m/s)^2 - (284\ m/s)^2\\a = \frac{-(284\ m/s)^2)}{(2)(178\ m)}\\\\[/tex]
a = 226.56 m/s²
b)
Now, we can find the force by Newton's Second Law:
[tex]F = ma\\F = (84\ kg)(-226.56\ m/s^2)\\[/tex]
F = - 19031.04 N = - 19 KN
Here, negative sign shows braking force.
a)
For work done:
[tex]Work = W = Fs\\W = (-19031.04\ N)(178\ m)\\[/tex]
W = - 3387525.12 J = - 3.39 MJ
