FYKOS Year 30 Series 3 Problem 4 — free radar · FYKOS 30 #30.3.4
Physics · mechanics · optics
Problem
A red marker is placed on every bollard along a road (wavelength of the red colour used is λr=630nm). When the driver of a passing car sees the marker as blue (wavelength λb=450nm), she knows that she is speeding. What is the car's speed when this happens? What is the momentum and kinetic energy of a typical passenger car at this speed?