A certain car is capable of accelerating at a rate of +0.90 m/s2. How long does it take for this car to go from a speed of 55 mi/h to a speed of 80 mi/h?
It is mainly a matter of units conversion.
Decide on what units you'd like to use for the final answer (usually seconds for cars). Convert everything to metres and seconds and use
time = (final velocity - initial velocity) / acceleration
To change from mph to m/s
multiply by
63360*0.0254/3600
=0.44704
I get 12.4 seconds
To calculate the time it takes for the car to go from a speed of 55 mi/h to 80 mi/h, we need to follow these steps:
Step 1: Convert the speeds from miles per hour to meters per second.
To convert miles per hour (mi/h) to meters per second (m/s), we can use the conversion factor:
1 mi/h = 0.44704 m/s
So, the initial speed of the car (55 mi/h) in meters per second is:
55 mi/h * 0.44704 m/s = 24.5872 m/s
And the final speed of the car (80 mi/h) in meters per second is:
80 mi/h * 0.44704 m/s = 35.7248 m/s
Step 2: Calculate the change in velocity (Δv).
The change in velocity (Δv) is the final velocity minus the initial velocity. In this case:
Δv = 35.7248 m/s - 24.5872 m/s = 11.1376 m/s
Step 3: Use the formula to calculate the time (t).
The formula to calculate the time is:
t = Δv / a
where Δv is the change in velocity and a is the acceleration.
In this case, the acceleration is given as +0.90 m/s^2 (positive because it's accelerating).
Substituting the values into the formula:
t = 11.1376 m/s / 0.90 m/s^2
Step 4: Calculate the time (t).
Divide the change in velocity by the acceleration:
t = 11.1376 m/s / 0.90 m/s^2 = 12.375 seconds
Therefore, it takes approximately 12.375 seconds for the car to go from a speed of 55 mi/h to a speed of 80 mi/h.