Solving a problem in physics section 39 paragraph 10 el

Solving a problem in physics section 39 paragraph 10 el

10. The heater of an electric kettle has two sections. When you turn on one of them in a pot to boil water after a time t1 = 15 min, when the other - after a time t2 = 30 min. How long tzakipit water in the kettle, if you include the two sections: a) series; b) in parallel?

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Detailed solution. Decorated in Microsoft Word 2003. (Target decided to use formula editor)