One for every 10 mph or yo can use the counting between landmarks method which does essentially the same thing since following distance would increase with speed.
7 car lengths
car lengths
It is more like car length than seconds when following another car. You should be at least 2 car lengths from the other car.
Don't worry about car lengths (too difficult to judge), maintain at least two seconds of separation between yourself and any vehicle in front of you, regardless of the speed.
Car lengths
One car length for every 10 mph.
At least 3 to 5 seconds, that would be at least 4 to 6 car lengths going freeway speed.
One car length for every 10 miles per hour of speed. If you are then traveling at 50 mph, one should allow at least 5 car lengths between you and the car in front of you.
32-36 moer or less
Depends on weather conditions and how fast your going: Perfect/near perfect conditions: 0-30mph 3 car lengths 30-60mph 6 car lenths Raining/fog: 0-30mph 5 car lengths 30-60mph 8 car lengths Snowing/Icey conditions 0-30mph 8 car lengths 30-60mph 11 car lengths
Standard distance for parking from hydrant is 2 car lengths. Page 67 of the Maryland Drivers Handbook states you must be 15 feet from a fire hydrant, that is about 1 car length.
20 meters would be equal to about 3 to 3.5 car lengths. A car length is about 20 feet. A meter is equal to about 3 feet 6 inches.