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Consider a circular wire loop of radius ...

Consider a circular wire loop of radius R, mass kept at rest on a rough surface . Let 1 be the current flowing through the loop and `vec(B) ` be the magnetic field acting along horizontal as shown in Figure. Estimate the current I that should be applied so that one edge of the loop is lifted off the surface ?

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when the current is passed through the loop. The torque is produced. If the torque acting on the loop is increased then the loop will start to rotate . The loop will start of lift if and only if the magnitude of magnetic torque due to current applied equals to the gravitational torque as shown in Figure
` tau_("magnetic ") = tau_("gravitational ")`
I A B = mg R
But `p_(m) ` = I A = I `(pi R^(2)) rArr pi I R^(2)` B = mg R
`rArr I = (mg )/(pi R B)`
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Consider a circular wire loop of radius R, mass m kept at rest on a rough surface. Let I be the current flowing through the loop and vec(B) be the magnetic field acting along horizontal as shown in Figure. Estimate the current I that should be applied so that one edge of the loop is lifted off the surface?

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Knowledge Check

  • A circular loop has radius R and a current I flows through it. Another circular loop has radius 2R and a current 2I flows through it. Ratio of the magnetic fields at their centres is

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