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abstrakt!
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Homework Statement
A magnetic field passes through a circular loop of radius 14 cm and makes an angle of 65° with respect to the plane of the loop. The magnitude of the field is given by the equation:
B = (1.25t2 - .500t + 4.00)T.
a) Determine the voltage induced in the loop when t = 2.00 s.
b) What is the direction of the current induced in the loop?
Homework Equations
[tex]ξ = -\frac{d∅}{dt}[/tex] where ξ is the induced voltage and ∅ is the magnetic flux.
Acircle = πr2
The Attempt at a Solution
My thinking is that area of the circle is not changing with respect to time, however, the magnetic flux is as it is a function of time. I have attempted various avenues (including simply plugging and chugging into BAcosΘ) but have not figured out how to solve this.
I wanted to use the rate of change relationship and attempted to derive an equation that I could use to solve this, however, I am stuck.
I possibly made an error in my derivative but I also need confidence whether I am on the right track or not.
[tex]-\frac{d∅}{dt} = -\frac{d}{dt}[BA cosΘ][/tex]
Using product rule, I get:
[tex]ξ = -[(\frac{dB}{dt}A cosΘ) + B(\frac{dA}{dt}cosΘ-AsinΘ)][/tex]
[tex]\frac{dB}{dt} = (2.5t +.500)T[/tex]
[tex]\frac{dA}{dt} = 2πr[/tex]
Plugging in:
-[(2.5t+.500(π(.14)2cos 65°) + (1.25t2 +.500t +4.00) (2π(.14) cos 65° - π(.14)2 sin 65°)] when t = 2.00 s
This looks incorrect and since the area is not changing I am not sure that I should be taking the derivative of the area.
The answer is supposedly 251 mV but I cannot get close to this and I am honestly quite stuck at this point.
I am either over-complicating this, making some careless mistakes or simply not understanding the nature of the problem.
Any help would be appreciated! Thank you for your time and assistance!