**1. The problem statement, all variables and given/known data**

A mass is attached to a spring through which circulates an electric current. Will the mass move?

**2. Relevant equations**

F = I l [itex]\times[/itex] B ?

**3. The attempt at a solution**

A spring is geometrically equivalent to a solenoid. Therefore, the current would generate a magnetic field which goes through the spring. What I’m not sure of is whether this magnetic field exerts a force on the solenoid or not.

Thank you.

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