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tensa zangetsu [6.8K]
3 years ago
14

A 0.12-kg metal rod carrying a current of current 4.1 A glides on two horizontal rails separation 6.3 m apart. If the coefficien

t of kinetic friction between the rod and rails is 0.18 and the kinetic friction force is 0.212 N , what vertical magnetic field is required to keep the rod moving at a constant speed of 5.1 m/s
Physics
1 answer:
Neporo4naja [7]3 years ago
7 0

Answer:

The magnetic field is B  =  8.20 *10^{-3} \  T

Explanation:

From the question we are told that

   The  mass of the metal rod is  m  = 0.12 \ kg

    The current on the rod is  I  = 4.1 \ A

    The distance of separation(equivalent to length of the rod ) is L   = 6.3 \ m

     The coefficient of kinetic friction is \mu_k  =  0.18

      The kinetic frictional force is  F_k  = 0.212 \ N

     The constant speed is v  = 5.1 \ m/s

Generally the magnetic force on the rod is mathematically represented as  

      F  =  B * I  *   L

For  the rod to move with a constant velocity the magnetic force must be equal to the kinetic frictional force so

        F_ k  =  B*  I  *  L

=>      B  =  \frac{F_k}{L  *  I  }

=>       B  =  \frac{0.212}{ 6.3   *  4.1   }

=>       B  =  8.20 *10^{-3} \  T

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Explanation:

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3 years ago
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