Microwave Ovens: Solving Eq. E = Emax.cos(wt)

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The discussion focuses on the equation E = Emax.cos(wt), which describes the electric field generated by a magnetron in microwave ovens. To solve for Emax, one must rearrange the equation to Emax = E/cos(wt) and input known values for E and wt. The initial confusion arises from misunderstanding the equation's purpose, as it cannot directly yield Emax without the initial electric field value. Additional relevant equations for microwave ovens include the power equation P = IV and the specific heat equation Q = mcΔT, which are important for understanding power output and heating processes. Clarification on these equations aids in the report preparation on microwave ovens.
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Hi I'm doing a report on microwave ovens and we have to include relevant equations in our reports. I've seen this on: http://www.lsbu.ac.uk/water/microwave.html and I've tried to use it to solve for Emax since (i think) i know the others, e.g.

4000v is applied across the magnetron so I am guessing this is the E, the angular frequency is 2pi x 2450x10^6, and t is the time you leave the microwave oven on for i think? Anyway it doesn't work and we have never studied this equation in class so I am very confused. Any help would be appreciated and any other relevant equations for microwave ovens would be great.
 
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Thanks!The equation you're trying to use is an equation for the electric field (E) generated by a magnetron as a function of time (t). It's not an equation that can be used to solve for E_max, since it only describes the rate of change of E over time. In order to solve for E_max, you would need to know the initial value of E at t=0, and then calculate the maximum value of the electric field as a function of time.
 


Hi there,

Thank you for reaching out for help with your report on microwave ovens. The equation you mentioned, E = Emax.cos(wt), is known as the electric field equation for a microwave. As you correctly stated, Emax represents the maximum electric field strength, w represents the angular frequency, and t represents time.

To solve for Emax, you will need to rearrange the equation to isolate Emax. This can be done by dividing both sides by cos(wt), giving you E/ cos(wt) = Emax. From there, you can plug in the values you have for E and wt to solve for Emax.

In terms of other relevant equations for microwave ovens, you may also want to consider the power equation, P = IV, where P represents power, I represents current, and V represents voltage. This equation can help you calculate the power output of the microwave, which is an important factor in its heating capabilities.

Additionally, you may want to look into the specific heat equation, Q = mcΔT, where Q represents heat energy, m represents mass, c represents specific heat capacity, and ΔT represents the change in temperature. This equation can help you understand the heating process of food in a microwave oven.

I hope this helps clarify the electric field equation for you and provides some additional equations to consider for your report. Good luck with your project!
 
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