Question

A car accelerates uniformly from 0 to 75 km/h in 15 seconds. a) What is the acceleration of the car in m/s2? B) What is the position of the car by the time it reaches the velocity of 75 km/h?

Answer 1

To find the acceleration of the car, we'll use the formula:

$\text{Acceleration}=\frac{\text{Change in Velocity}}{\text{Change in Time}}$

a) First, let's convert the initial and final velocities from km/h to m/s:

Initial velocity ($v_i$) = 0 km/h = 0 m/s Final velocity ($v_f$) = 75 km/h

To convert km/h to m/s, we multiply by $\frac{1000}{3600}$ (since 1 km/h = $\frac{1000}{3600}$ m/s):

$v_f=75\times \frac{1000}{3600}=20.83\text{m/s}$

Now, let's calculate the acceleration:

Acceleration=vf−vit=20.83−015=1.39 m/s2 ext{Acceleration} = frac{{v_f - v_i}}{{t}} = frac{{20.83 - 0}}{{15}} = 1.39 , ext{m/s}^2Acceleration=t<span class="frac-line"