Physics in the Kitchen

Physics in the Kitchen

Physics extends well into your everyday life, describing the motion, forces and energy of ordinary experience. We use Physics every day when we are walking, watching, listening, cooking and also in the technology we use.

Can Physics be in action in our homes like the kitchen? Absolutely! There are many appliances in our kitchen that use Physics to make our daily lives more convenient. Here are 3 such appliances that have a place in almost all kitchens.

 

Refrigerators

Have you ever stopped to think how our fridges keep cool even in Singapore’s hot weather? Food goes bad because bacteria breed inside it. But bacteria grow slower at lower temperatures, so the cooler you can keep food, the longer it will last.

A refrigerator keeps food cool with a coolant system. The refrigerant circulating inside is changed from a liquid into a gas via a process called evaporation. That cools the surrounding area and produces the desired effect. All the time your refrigerator is humming away, liquid refrigerant is turning into cool gases, water is turning into ice, and your food is staying deliciously fresh. 

 

Induction Stove Tops

How can you create heat without fire? Physics! More specifically, electromagnetism. If you put certain materials into a rapidly alternating magnetic field, the material absorbs the energy and heats up. That’s because the field creates electrical currents inside the material, and the resistance of the material converts this electrical energy into heat, which is transferred to the food inside the pan.

Induction cooktops use this to heat food without any flames or direct heat, cooking more efficiently than gas stoves.

 

Microwave Ovens

This nifty little invention is probably a life saver for many busy families when you need to get warm food on the dinner table fast! So what’s taking place inside? The secret here are the microwaves.

These devices use microwave radiation. Created in a device called the magnetron, these waves get water excited. When a microwave hits a water molecule, the molecule absorbs it and moves faster, and the water heats up.

Microwave ovens heat the water within the food, so it heats up quicker. They  also penetrate into the food, effectively heating it from within.

So the next time you eat a cold slice of watermelon or heat up leftovers, give some appreciation for these unassuming pieces of engineering that make our lives so much more convenient!