1. A microwave uses standing electromagnetic waves to cook food. Assume the wavelength is 12.2 cm. a. What is the frequency of the standing waves (Hz)? b. Write down equations for the electric and magnetic standing waves (use variables for Emax, Bmax). c. How long must the cavity be to contain 5 nodes? d. Assume the maximum electric field strength is Emax=2.0 kV/m. Estimate the maximum magnetic field and maximum power density (W/m²).

1. A microwave uses standing electromagnetic waves to cook food. Assume the wavelength is 12.2 cm. a. What is the frequency of the standing waves (Hz)? b. Write down equations for the electric and magnetic standing waves (use variables for Emax, Bmax). c. How long must the cavity be to contain 5 nodes? d. Assume the maximum electric field strength is Emax=2.0 kV/m. Estimate the maximum magnetic field and maximum power density (W/m²).

University Physics Volume 2

18th Edition

ISBN:9781938168161

Author:OpenStax

Publisher:OpenStax

Chapter16: Electromagnetic Waves

Section: Chapter Questions

Problem 94AP: A certain microwave oven projects 1.00 kW of microwaves onto a 30-cm-by-40-cm area. (a) What is its...

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