A car, moving along a straight stretch of highway, begins to accelerate at 0.0218 m/s
2
. It
takes the car 86 s to cover 2 km.
How fast was the car going when it first
began to accelerate?
Answer in units of m/
To find how fast the car was going when it first began to accelerate, we need to calculate its initial velocity.
First, let's convert the distance covered by the car from kilometers to meters:
2 km = 2000 m
Next, let's determine the final velocity of the car after 86 seconds using the equation of motion:
vf = vi + at
Here,
vf = final velocity,
vi = initial velocity,
a = acceleration,
t = time.
Given that:
a = 0.0218 m/s^2,
t = 86 s,
we can rearrange the equation to solve for vf:
vf = vi + at
vf - at = vi
Substituting the given values:
vi = vf - at
vi = 0 + (0.0218 m/s^2) * (86 s)
vi = 1.8768 m/s
So, the car was going 1.8768 m/s when it first began to accelerate.