1. The problem statement, all variables and given/known data Here's the question for my coursework. "Everyone knows the feeling of getting into a car that has been under the hot sun.Nobody likes it. Design an experiment and investigate the factor(s) that contribute to this condition." Here's my question, 1)Do window tint really helps in reducing the heat entering the car since UV, visible light and IR were blocked? 2)Do the darker tint reduce more heat? (From what I have done in my experiment, darker tint didn't seem to better in heat reduction, they are approximately the same as lighter tint, or even worse.) Is that true? 2. The attempt at a solution I have carried out an experiment by building 5 model miniature cars of equal size using cardboard and 4 of them were put on window tint of different VTL (Visible Light transmittance), while the last one was put on a plastic cover of approximately the same thickness to represent the non tinted glass. After that, 5 of them were put under the sun and the temperature inside the car is observed. (ps: no glasses were used, I simply glued the window tints/plastic covers.) And the result I got was the non tinted (plastic cover) did has a little bit higher temperature than the rest. The non tinted car has around 55°c while the rest were slightly lower (52-53 °C).