When Kai puts the cheese on the hamburger, it begins to melt because of conduction. The hamburger already has heat inside of it so when the cheese touches the hamburger, heat transfers from the hamburger to the cheese through conduction.
The piece of cheese melts when it’s placed on the hamburger because conduction occurs. The hamburger is warmer than the cheese, so thermal energy is transferred from the hamburger to the cheese, causing it to melt.
