With the UK experiencing soaring temperatures of 30°C, cars can become dangerously hot. Mathematician and broadcaster Hannah Fry has proposed a simple yet effective technique for cooling vehicles without air conditioning. By opening a window and rapidly opening and closing the driver's door, the trapped hot air can be expelled, creating a flow of cooler air into the vehicle. This method relies on the principles of thermodynamics, where the motion of the door creates low pressure that draws out the hot air. Fry shared her experience on social media, stating her car felt 'beautifully temperate' after using this technique. The recent heat wave is attributed to high-pressure systems that compress air, raising temperatures across the UK. Additionally, experts suggest that fans can be more effective when pointed out of windows to push hot air outside, especially during the day. Once outside temperatures drop, reversing the fan's direction can help draw in cooler air, enhancing comfort indoors.