To measure the speed of an approaching car a police officer shines?
Alight waves on it
Bradio waves on it
Cmicrowaves on it
Dultra high frequency waves on it
Correct answer
B. radio waves on it
Explanation
Radar, which stands for radio detection and ranging, is a system that uses reflected radio waves to detect objects and measure their distance and speed. For example, police use radar to calculate the speed of cars.