What current in a solenoid 15-cm long wound with 100 turns would produce a magnetic field equal to that of the Earth, 5 cross times 10 to the power of negative 5 end exponentT ?

The value is    

Explanation:

From the question we are told that

    The length of the solenoid is

     The number of turns is  

      The  magnetic field of the earth is  

Gnerally magnetic field is mathematically represented as

=>        

=>          

=>          

b.a device that inputs heat into a cool object