View Full Document


Unformatted text preview:

FEATURES www iop org journals physed Microwave oven experiments with metals and light sources Michael Vollmer Klaus Peter M llmann and Detlef Karst dt Physikalische Technik Fachhochschule Brandenburg Magdeburger Stra e 50 14770 Brandenburg Germany E mail vollmer fh brandenburg de Abstract Don t put metal objects in the microwave is common safety advice But why Here we describe demonstration experiments involving placing household metallic objects in a microwave oven These allow a better understanding of the interaction of microwaves with materials Light bulbs and discharge lamps can also be used in instructive demonstrations M This article features online multimedia enhancements Introduction The physics of microwave ovens and cooking with microwaves has been the topic of three recent articles 1 3 A selection of demonstrations has already been included in the second and third of these however microwave ovens abbreviated hereafter as microwaves allow a huge variety of other experiments which may serve as lecture demonstrations in the classroom 4 There are also many related websites with images and sometimes video clips e g 5 7 each giving further links Since microwaves are part of many students everyday lives they are a suitable topic to raise and or stimulate interest in physics Many of the experiments can be performed with little additional equipment Some however use a thermal infrared camera 8 to visualize temperature differences in extended objects In order to visualize the processes within a microwave oven we also modified a commercial microwave by replacing part of the door with an infrared transparent window Since part of the metal grid is absent some radiation will leak out For safety reasons a large distance is required between the observers and the camera microwave We have still included some of these experiments 500 PHYSICS EDUCATION 39 6 in order to give an insight into the physics We emphasize that this modified oven should not be rebuilt and experiments

Access the best Study Guides, Lecture Notes and Practice Exams

Loading Unlocking...

Join to view Metals and light sources and access 3M+ class-specific study document.

We will never post anything without your permission.
Don't have an account?
Sign Up

Join to view Metals and light sources and access 3M+ class-specific study document.


By creating an account you agree to our Privacy Policy and Terms Of Use

Already a member?