How would you prove air contains carbon dioxide??​

by using lime water

Explanation:

if carbon dioxide is bubbled through lime water then the water turns from clear to a milky, cloudy color. this is why when used in a simple respirometer it can show that there's more carbon dioxide in exhaled air compared to inhaled air

r=rho l/a where a is the area, l is the length and rho is resistivity so the greater the area the lesser the resistance thats why the earth pin is thicker bcos current follow the shortest path, so less resistive .

12000j is work done