If a car accelerates at [tex]4.5 \, \text{m/s}^2[/tex] to the right and speeds up by a total of [tex]99 \, \text{m/s}[/tex] to the right, how long was it accelerating?



Answer :

To solve this problem, we need to determine how long the car was accelerating. We know the following details:

- The acceleration (a) of the car is 4.5 m/s².
- The total speed increase (Δv) is 99 m/s.

We can use the kinematic equation that relates acceleration, change in velocity, and time. The relevant formula here is:

[tex]\[ \Delta v = a \cdot t \][/tex]

Where:
- [tex]\(\Delta v\)[/tex] is the change in velocity,
- [tex]\(a\)[/tex] is the acceleration,
- [tex]\(t\)[/tex] is the time.

We need to find the time [tex]\(t\)[/tex]. We can rearrange the formula to solve for [tex]\(t\)[/tex]:

[tex]\[ t = \frac{\Delta v}{a} \][/tex]

Substituting the given values into the equation:

[tex]\[ t = \frac{99 \text{ m/s}}{4.5 \text{ m/s}^2} \][/tex]

By performing this division, we get:

[tex]\[ t = 22.0 \text{ seconds} \][/tex]

So, the car was accelerating for 22.0 seconds.