To determine how long it takes for a car to reach a speed of 80 feet per hour (ft/hr), we need to know the acceleration of the car. Acceleration is the rate at which velocity changes over time.
Let's assume the car starts from rest (zero velocity) and accelerates uniformly until it reaches the speed limit of 80 ft/hr. We'll also assume that there are no other factors affecting the acceleration, such as friction or air resistance.
The formula to calculate the time it takes for an object to reach a certain velocity under constant acceleration is:
time = (final velocity - initial velocity) / acceleration
In this case, the initial velocity is 0 ft/hr, the final velocity is 80 ft/hr, and we need to know the acceleration of the car.
Without the specific acceleration value, we cannot provide an exact time. If you have the acceleration value, please provide it so that I can help you calculate the time it takes for the car to reach 80 ft/hr.