If your car accelerates from rest at a steady rate of 4 m/s2, how soon will it reach 84 km/h
See your previous post.
To find out how soon the car will reach 84 km/h (or any other speed), we can use the kinematic equation which relates acceleration, initial velocity, time, and final velocity.
The equation we'll use is:
final velocity = initial velocity + (acceleration * time)
In this case, the initial velocity is 0 m/s since the car starts from rest, the acceleration is 4 m/s^2, and the final velocity is given as 84 km/h.
First, we need to convert the final velocity from km/h to m/s. We'll use the conversion factor of 1 km/h = 1000 m/3600 s:
84 km/h * (1000 m/3600 s) = 23.33 m/s
Now we can rearrange the equation to solve for time:
time = (final velocity - initial velocity) / acceleration
time = (23.33 m/s - 0 m/s) / 4 m/s^2
time = 5.83 seconds
Therefore, the car will reach 84 km/h in approximately 5.83 seconds.