A car traveling at 60 mph accelerates to pass a truck. Five seconds later, the car reaches 80 mph. Calculate the car's acceleration.

To calculate the acceleration of the car, we need to know two things: the change in velocity (which is the final velocity minus the initial velocity) and the time over which this change occurs.

The formula to calculate acceleration (a) is: \[ a = \frac{\Delta v}{t} \] where: - \( \Delta v \) is the change in velocity - \( t \) is the time in seconds

From the information given: - The initial velocity (v_i) is 60 mph - The final velocity (v_f) is 80 mph - The time (t) is 5 seconds

First, we will convert the velocities from miles per hour to feet per second (since acceleration is generally measured in feet per second squared in the US customary system or meters per second squared in the metric system):

1 mile per hour is approximately equal to 1.467 feet per second.

So, Initial velocity in fps = 60 mph * 1.467 fps/mph = 88.02 fps Final velocity in fps = 80 mph * 1.467 fps/mph = 117.36 fps

Now that we have both velocities in feet per second, we can find the change in velocity: \[ \Delta v = v_f - v_i = 117.36 fps - 88.02 fps \] \[ \Delta v = 29.34 fps \]

Next, we use the acceleration formula with our values for \( \Delta v \) and \( t \): \[ a = \frac{29.34 fps}{5 s} \] \[ a = 5.868 fps^2 \]

So, the car's acceleration is approximately 5.868 feet per second squared.