Emf in an ac generator (20-7)

Question 1 of 7

Question

Angular speed of the rotating coil

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Question

Angle of the coil at $t = 0$

{"title":"Emf produced by an ac generator","description":"Wrong","type":"incorrect","color":"#99CCFF","code":"[{\"shape\":\"poly\",\"coords\":\"82,133\"},{\"shape\":\"rect\",\"coords\":\"10,16,12,16\"},{\"shape\":\"poly\",\"coords\":\"144,22\"},{\"shape\":\"rect\",\"coords\":\"2,13,13,32\"}]"} {"title":"Angular speed of the rotating coil","description":"Wrong","type":"incorrect","color":"#ffcc00","code":"[{\"shape\":\"rect\",\"coords\":\"45,8,72,31\"},{\"shape\":\"rect\",\"coords\":\"201,13,225,29\"}]"} {"title":"Time","description":"Incorrect","type":"incorrect","color":"#333300","code":"[{\"shape\":\"rect\",\"coords\":\"223,7,237,30\"}]"} {"title":"Angle of the coil at t = 0","description":"Correct!","type":"correct","color":"#000080","code":"[{\"shape\":\"rect\",\"coords\":\"267,5,291,36\"}]"} {"title":"Magnitude of the magnetic field to which the coil is exposed","description":"Incorrect","type":"incorrect","color":"#333333","code":"[{\"shape\":\"rect\",\"coords\":\"121,4,143,29\"}]"} {"title":"Area of the coil","description":"Incorrect","type":"incorrect","color":"#800000","code":"[{\"shape\":\"rect\",\"coords\":\"97,2,119,29\"}]"} {"title":"Number of turns in the coil","description":"Incorrect","type":"incorrect","color":"#FF6600","code":"[{\"shape\":\"rect\",\"coords\":\"74,3,95,29\"}]"}

Review

The emf alternates with angular frequency $\omega$ , the same as the angular speed of the rotating coil. The maximum value of the emf is $\epsilon_{\mathrm{max}} = \omega NAB$ , which shows that we can increase the maximum emf by increasing the angular speed $\omega$ , the number of turns $N$ , the coil area $A$ , the magnetic field magnitude $B$ , or a combination of these.