Question

A car initially traveling at 25 m/s speeds up to 60 m/s under a uniform acceleration of 5.0 m/s2 to avoid being hit by another car. How long does it take the car to speed up and get out of the way? Show your work.

Answer 1

Answer:

The car takes 7 seconds to speed up and get out of the way

Explanation:

Constant Acceleration Motion

It's a type of motion in which the velocity of an object changes uniformly over time.

Having a as the constant acceleration, vo the initial speed, vf the final speed, and t the time, the following relation applies:

v_f=v_o+at

Using the above equation we can solve for t:

$\displaystyle t=\frac{v_f-v_o}{a}$

The car has an initial speed of vo=25 m/s and ends up at vf=60 m/s with an acceleration of a=5 $m/s^2$.

Given all the appropriate data, calculate t:

$\displaystyle t=\frac{60-25}{5}$

Calculating:

$\displaystyle t=\frac{35}{5}$

t = 7 seconds

The car takes 7 seconds to speed up and get out of the way