Can you break a microwave if you turn it on and forget to put the food in it?

Yes, you can potentially damage a microwave by running it empty. Microwaves work by generating electromagnetic waves that heat food, and without food or a container inside to absorb this energy, the microwaves can reflect back into the magnetron, which is the component that produces the microwaves. This can lead to overheating and may cause permanent damage to the microwave. It's always best to ensure there is food or a microwave-safe container inside before operating the appliance.