A person wants to roll a solid non-conducting spherical ball of mass m and radius r on a surface whose coefficient of static friction is μ . He placed the ball on the surface wrapped with n turns of closely packed conducting coils of negligible mass at the diameter. By some arrangement he is able to pass a current i through the coils either in the clockwise direction or in the anti-clockwise direction. A constant horizontal magnetic field B is present throughout the space as shown in the figure. (Assume μ is large enough to help rolling motion) The minimum value of μ for which the rolling motion is possible, is

A person wants to roll a solid non-conducting spherical ball of mass m

1.	A person wants to roll a solid non-conducting spherical ball of mass m and radius r on a surface whose coefficient of static friction is μ . He placed the ball on the surface wrapped with n turns of closely packed conducting coils of negligible mass at the diameter. By some arrangement he is able to pass a current i through the coils either in the clockwise direction or in the anti-clockwise direction. A constant horizontal magnetic field B is present throughout the space as shown in the figure. (Assume μ is large enough to help rolling motion) The minimum value of μ for which the rolling motion is possible, is
Answer» A person wants to roll a solid non-conducting spherical ball of mass m and radius r on a surface whose coefficient of static friction is $μ$ . He placed the ball on the surface wrapped with n turns of closely packed conducting coils of negligible mass at the diameter. By some arrangement he is able to pass a current i through the coils either in the clockwise direction or in the anti-clockwise direction. A constant horizontal magnetic field B is present throughout the space as shown in the figure. (Assume $μ$ is large enough to help rolling motion) The minimum value of $μ$ for which the rolling motion is possible, is

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