Haley is driving down a straight highway at 73 mph. A construction sign warns that the speed limit will drop to 55 mph in 0.50 mi.
What constant acceleration (in m/s2) will bring Haley to this lower speed in the distance available?

We know Haley is driving with an initial velocity of [tex]V_{o}=73mi/h[/tex] and then she has to change to a velocity of [tex]V_{f}=55mi/h[/tex] in a distance [tex]d=0.50 mi[/tex], and we also know we are dealing with constant acceleration [tex]a[/tex].

Therefore, the following equation will be useful:

[tex]{V_{f}}^{2}={V_{o}}^{2}+2ad[/tex] (1)

Clearing [tex]a[/tex]:

[tex]a=\frac{{V_{f}}^{2}-{V_{o}}^{2}}{2d}[/tex] (2)

[tex]a=\frac{{(55mi/h)}^{2}-{(73mi/h)}^{2}}{2(0.50 mi)}[/tex] (3)

[tex]a=-2304 mi/h^{2}[/tex] (4)

Knowing [tex]1h=3600 s[/tex] and [tex]1mi=1609.34 m[/tex]:

[tex]a= -1029.97 m/s^{2}[/tex] this is the constant acceleration that will bring Haley to lower speed

Haley is driving down a straight highway at 73 mph. A construction sign warns that the speed limit will drop to 55 mph in 0.50 mi. What constant acceleration (in m/s2) will bring Haley to this lower speed in the distance available?

Respuesta :

Otras preguntas

Haley is driving down a straight highway at 73 mph. A construction sign warns that the speed limit will drop to 55 mph in 0.50 mi.
What constant acceleration (in m/s2) will bring Haley to this lower speed in the distance available?