Speed checking incoming cars

by **futurecop** on Fri Aug 24, 2007 5:51 pm

Obviously you can check the speed of a car coming toward you with a radar. Is this possible if the incoming car is in the other lane? If so, how does this work exactly?

by **Ryan_W** on Mon Aug 27, 2007 11:42 pm

Hi,

You will be able to use a radar gun to detect the speed of an oncoming car regardless of the lane they are in, as long as you are really good with basic Trigonometry. The farther you get away from the direct line of travel, the lower the registered speed will be. When using a radargun, try and stand within 10 degrees of the path of the oncoming vehicle to reduce the cosine effect (reduction of registered sped due to angle) and get a more accurate reading.

Basically, if a car is travelling towards you at 60mph, and you are standing 20 degrees from the direction of travel, you will get a reading of 56mph.