Suppose your car accelerates from rest to 9 m/s in 2 s. Assume that the acceleration is constant in this time interval. A. What is the acceleration of your car? Express your answer in m/s 2 . B. How far will you travel in 2 s? Express your answer in meters.

Respuesta :

Answer :

(a) The acceleration of the car is, [tex]4.5m/s^2[/tex]

(b) The distance covered by the car is, 9 m

Explanation :  

By the 1st equation of motion,

[tex]v=u+at[/tex] ...........(1)

where,

v = final velocity = 9 m/s

u = initial velocity  = 0 m/s

t = time = 2 s

a = acceleration of the car = ?

Now put all the given values in the above equation 1, we get:

[tex]9m/s=0m/s+a\times (2s)[/tex]

[tex]a=4.5m/s^2[/tex]

The acceleration of the car is, [tex]4.5m/s^2[/tex]

By the 2nd equation of motion,

[tex]s=ut+\frac{1}{2}at^2[/tex] ...........(2)

where,

s = distance covered by the car = ?

u = initial velocity  = 0 m/s

t = time = 2 s

a = acceleration  of the car = [tex]4.5m/s^2[/tex]

Now put all the given values in the above equation 2, we get:

[tex]s=(0m/s)\times (2s)+\frac{1}{2}\times (4.5m/s^2)\times (2s)^2[/tex]

By solving the term, we get:

[tex]s=9m[/tex]

The distance covered by the car is, 9 m