Question

In 1991 four English teenagers built an eletric car that could attain a speed of 30.0m/s. Suppose it takes 8.0s for this car to accelerate from 18.0m/s to 30.0m/s. What is the magnitude of the car's acceleration?

Answer 1

Answer:

Acceleration of the car, $a=1.5\ m/s^2$

Explanation:

It is given that,

Initial speed of the car, u = 18 m/s

Final speed of the car, v = 30 m/s

Time taken, t = 8 s

We need to find the acceleration of the car. Let it is given by a. It can be calculated using the first equation of motion.

$v=u+at$

Where

a is the acceleration of the car.

$a=\dfrac{v-u}{t}$

$a=\dfrac{30-18}{8}$      

$a=1.5\ m/s^2$

So, the magnitude of the car's acceleration is $1.5\ m/s^2$. Hence, this is the required solution.                                          

Answer 2

a=Δv/Δt=(30.0-18.0)/8.0=12.0/8.0=1.5 m/s²