Keep a Space
At 35 mph you travel
51 feet in 2 seconds. That means if you are driving 35 mph
you need to be 102 ft. behind the vehicle in front of you
in order to be able to percieve and avoid an obstacle. You
can either pick an object that passes the vehicle in front
of you and count "one-thousand-one, one-thousand-two."
or count dashed center lines between the vehicle and yours.
Dashed lines are 10 feet long and are 30 feet apart. Therefore,
every dashed line represents an additional 40 feet between
If you are going
35 mph and need to be at least 102 feet, about 3 dashed
lines (3 dashed lines = 3 x 40 feet = 120 feet), behind
yourself and the vehicle in front of you.
When traveling at
70 mph, use a 4 second interval. In 4 seconds there should
about 410 feet between yourself and the vehicle in front
of you. That is a little more that 5 dashed lines (5 x 40
= 200 feet).