HELP Elctromagnetic Questions

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To calculate the resistance of the wire loop, use the formula R = ρL/A, where ρ is the resistivity, L is the length of the wire, and A is the cross-sectional area. The resistivity is given as 2.15 x 10^-8 Ohm x m, and the radius of the wire is 0.40 mm, allowing for the calculation of the cross-sectional area. The dimensions of the rectangular loop and the magnetic field information are not necessary for determining resistance. The discussion emphasizes focusing on the relevant variables for resistance rather than extraneous details. Understanding these principles is crucial for solving the problem effectively.
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HELP ! Elctromagnetic Questions

Ok I need to solve for Resistance, but itseems like I don't have enough info
Here's my question :

The rectangular wire loop has dimensions of 4.0cm by 3.0cm. Moving at constant
speed, the loop completely exits the 0.14T uniform magnetic field in 0.12 seconds.
The wire has a radius of 0.40mm and a resistivity of 2.15 x 10^-8 Ohm x m .

Determine:

A) the resistance of the wire

Can you please help me with this ?
I have exam on following monday SO i need to get this ASAP !
THank you sooo much
 
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HELP ! Elctromagnetic Question

Ok I need to solve for Resistance, but itseems like I don't have enough info
Here's my question :

The rectangular wire loop has dimensions of 4.0cm by 3.0cm. Moving at constant
speed, the loop completely exits the 0.14T uniform magnetic field in 0.12 seconds.
The wire has a radius of 0.40mm and a resistivity of 2.15 x 10^-8 Ohm x m .

Determine:

A) the resistance of the wire

Can you please help me with this ?
I have exam on following monday SO i need to get this ASAP !
THank you sooo much
 
R=rho L/A. You know rho, L, and A.
 
You can figure it out using the rules for magnetic flux and emf.

\Phi = \iint \mathbf{B} \cdot d\mathbf{a}

which if the magnetic field is constant, then

\Phi = B*Area

then the emf would be

\epsilon = \frac{d \phi}{dt}

you can find the current with current density formulas and whatnot. Do some work, and we'll see how we can help you.
 
Do you perhaps mean you need the impedance of the wire? Otherwise for resistance most of the given information about the shape of the wire (loop) is superfluous as Pam suggests. Only rho, L, A determine the resistance, the other information has no effect.
 
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Starting with the mass considerations #m(t)# is mass of water #M_{c}# mass of container and #M(t)# mass of total system $$M(t) = M_{C} + m(t)$$ $$\Rightarrow \frac{dM(t)}{dt} = \frac{dm(t)}{dt}$$ $$P_i = Mv + u \, dm$$ $$P_f = (M + dm)(v + dv)$$ $$\Delta P = M \, dv + (v - u) \, dm$$ $$F = \frac{dP}{dt} = M \frac{dv}{dt} + (v - u) \frac{dm}{dt}$$ $$F = u \frac{dm}{dt} = \rho A u^2$$ from conservation of momentum , the cannon recoils with the same force which it applies. $$\quad \frac{dm}{dt}...
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