Air

 This adventure comes from an episode of the Grand Tour. Specifically, S1 ep2, where they are in South Africa discussing the Aston Martin Valkyrie and its horsepower to mass ratio (they say weight, but I do physics, so it is mass, as weight is a force, not a unit). It is a 1 to 1 ratio, 900hp to 900kg. If you go and Google the Valkyrie, you will find that it is very aerodynamic and therefore uses what is called downforce to generate its grip. You see, there are two types of grip, mechanical and aerodynamic grip. Mechanical grip is the grip of the tyre, and this is the grip in normal cars; only supercars and beyond make use of aerodynamic grip, as high speeds are required for an effect.   

In the episode, they spoke about hot air being thinner than cold air. Now, although this is literally just GCSE physics, it does make sense when you put your mind to it. As air molecules have more energy when the air is hot (greater internal energy) so that means that the air has a lower viscosity compared to cold air and vice versa from there with cold air.

However, why is this important for downforce? Well, you see if the air is thick (and volume is constant for both hot and cold air), then it is denser (for cold air), allowing the car to displace a greater mass of air, allowing it to generate more downforce, even surpassing the car's mechanical grip threshold. As a result, this allows for greater cornering speeds.

I realise that this is my first adventure in a long time, and I am not sure if it will continue at a constant rate, but I really enjoy blogging and will try to be more active on the platform.