Bending Wires and Magnetic Fields?

AI Thread Summary
The discussion revolves around a test question involving the magnetic fields generated by bent wires, with a focus on solving it quickly without calculators. Participants suggest using the Biot-Savart law but express doubts about its feasibility within the time constraints. The consensus is that only the vertical components of the magnetic field influence the center point, while symmetry indicates that the magnetic field from a half wire is half that of a full wire. This reasoning simplifies the problem significantly. The conversation emphasizes the importance of quick reasoning and symmetry in solving magnetic field problems efficiently.
albert1993
Messages
17
Reaction score
0

Homework Statement



see attached. this question is from a test that doesn't allow any calculators and usually makes students solve the problem in 1 minute max.

Homework Equations



perhaps biot savart is to be used? but I doubt that can be done in the time limit...

The Attempt at a Solution



Only the verticals affect the center? I don't know...
 

Attachments

  • Physics Help.png
    Physics Help.png
    8 KB · Views: 458
Physics news on Phys.org
Only the verticals affect the center. For the horizontals, by simple symmetry arguments would you agree that the magnetic field due to a half wire will be half that of a full wire? If so, then you are done!
 
Thank you!
 
TL;DR Summary: I came across this question from a Sri Lankan A-level textbook. Question - An ice cube with a length of 10 cm is immersed in water at 0 °C. An observer observes the ice cube from the water, and it seems to be 7.75 cm long. If the refractive index of water is 4/3, find the height of the ice cube immersed in the water. I could not understand how the apparent height of the ice cube in the water depends on the height of the ice cube immersed in the water. Does anyone have an...
Thread 'Variable mass system : water sprayed into a moving container'
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}...
Back
Top