You might be in good condition but what about the road condition (wet, icy), the state of you tyres (good tread or worn), the state of your brakes?
40 mph = 40 miles in 60 minutes = 20 miles in 30 minutes.
Just divide the distance by the speed.
Distance = Rate * Time or, for our purpose Time = Distance/Rate at 50 mph Time = 4.5 miles/50 mph = 0.09 hours = 5.4 minutes ----------------------------- at 40 mph Time = 4.5 miles/40 mph = 0.1125 hours = 6.75 minutes ---------------------------------------------------- 6.75 - 5.4 = 1.35 minutes saved
Driving at 40 mph for 50 minutes would mean covering a distance of: 40 x 50/60 = 33 1/3 miles.
The vehicle's reaction distance depends on the driver's reaction time.
44feet
You might be in good condition but what about the road condition (wet, icy), the state of you tyres (good tread or worn), the state of your brakes?
40 mph = 40 miles in 60 minutes = 20 miles in 30 minutes.
Stopping distance at 40mph = 36m
Just divide the distance by the speed.
Distance = Rate * Time or, for our purpose Time = Distance/Rate at 50 mph Time = 4.5 miles/50 mph = 0.09 hours = 5.4 minutes ----------------------------- at 40 mph Time = 4.5 miles/40 mph = 0.1125 hours = 6.75 minutes ---------------------------------------------------- 6.75 - 5.4 = 1.35 minutes saved
Since the two distances are equal, the average is (40 mph + 60 mph)/2 = 50 mph.
85 feet
Time = Distance/Speed = 25 miles/40 mph = 0.625 hours = 37.5 minutes.
Time = Distance/Speed = 40/60 hours = 40 minutes.
A good rule of thumb is to keep a distance of one car length, about 10 feet, for every 10 mph of speed, so at 40 mph, you should be 40 feet behind the car in front of you. Obviously, this is harder to do in heavy traffic.