(a) [tex]-1.46\cdot 10^{-4} m/s^2[/tex]
The average acceleration of the ship is given by
[tex]a=\frac{v-u}{t}[/tex]
where
v is the final velocity
u is the initial velocity
t is the time elapsed
Here we have:
[tex]u=34 km/h =9.44 m/s[/tex] is the initial velocity
v = 0 is the final velocity
[tex]t=18 min =64800 s[/tex] is the time elapsed
Substituting, we find
[tex]a=\frac{0-9.44 m/s}{64800 s}=-1.46\cdot 10^{-4} m/s^2[/tex]
(b) 4.72 m/s
Assuming the acceleration is uniform, the average velocity of the ship is given by:
[tex]v_{avg} = \frac{v+u}{2}[/tex]
where
v is the final velocity
u is the initial velocity
Here we have:
v = 0
u = 9.44 m/s
So the average velocity of the ship is
[tex]v_{avg} = \frac{0+9.44 m/s}{2}=4.72 m/s[/tex]
