Answer:
-60 m/s²
Step-by-step explanation:
We are not given the velocity of the plane at landing but we are given velocities at two time periods
V₅, the velocity of the plane 5 seconds after landing is 110 m/s
Plugging this into the velocity equation we get
[tex]\bold{v_5 = a.5 + v_0 = 5a + v_0}[/tex] (1)
Similarly
[tex]\bold{v_{15} = a.15 + v_0 = 15a + v_0}[/tex] (2)
Subtract (1) from[tex]v_{15} - v_5 = (15a + v_0) - (5a + v_0) = (15a-5a) + (v_0-v_0) = 10a[/tex]
Therefore [tex]a = \frac{v_{15} - v_5}{10}[/tex]
Given [tex]v_{15}= 50 m/s \textrm{ and } v_5 = 110m/s[/tex]
this evaluates to
[tex]a = (50-110)/10 =[/tex] -60 m/s²
The negative value is because the plane is actually decelerating which is a negative number
