Understanding E(t) = wNBAsin(wt) and Its Variables

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The discussion focuses on understanding the equation E(t) = wNBAsin(wt) and its variables. Participants clarify that w represents angular frequency, A is the area, and N denotes the number of loops of wire. There is confusion regarding the variable B, which is identified as the magnetic field strength. The relationship between magnetic flux and induced electromotive force (emf) is also discussed, emphasizing that the emf is derived from the rate of change of magnetic flux. Overall, the conversation aims to clarify the definitions and roles of each variable in the equation.
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Homework Statement


Where can I find the defintion of the varaibles? I know w is the angular velocity, A is the Area, and t is time. but what are NB? is B the field strength? If that is so, then what is N?


Homework Equations





The Attempt at a Solution

 
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Hi lampshader! :wink:

Number of turns? :smile:
 
Number of cycles?

If I were to calculate the angular velocity; w = number of 'turns' / time it makes the 'turns'.

So the denominator is used again as B in, E(t) = wNBAsin(wt)?

Thanks! =)
 
I thought that, when I open my simulation (homework assignment), their are default values and a peak voltage is displayed. So, when I use the equation: E(t) = wNBAsin(wt); and calculate by subsituting in the default values, I am not getting the displayed peak voltage. Ya know?
 
Hi lampshader! :smile:

(have an omega: ω :wink:)
lampshader said:
… If I were to calculate the angular velocity; w = number of 'turns' / time it makes the 'turns'.

ah … now i see …

no, ω isn't a geometrical angular velocity, it's the frequency, of the variable magnetic field, Bcos(ωt).

So the magnetic flux is φ = NBAcos(ωt), and the emf is E(t) = dφ/dt = ωNBAsin(ωt). :smile:

(And N is the number of loops of the wire round the area A)
 
Thanks, I appreciate your time.
 
The book claims the answer is that all the magnitudes are the same because "the gravitational force on the penguin is the same". I'm having trouble understanding this. I thought the buoyant force was equal to the weight of the fluid displaced. Weight depends on mass which depends on density. Therefore, due to the differing densities the buoyant force will be different in each case? Is this incorrect?

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