Force on a Current-Carrying Wire

 
Parts List:      
1 current balance
(Pasco)
1 high current power supply
(BK Precission 1621A)
1 carbon plate rheostat 1 dial calipers
4 red banana plug wires 4 black banana plug wires 1 mg mass set 1 2-meter stick
1 vertical rod mounted to table edge 1 meter stick mounted vertically on rod    
Laser-based Optical Lever:    
1 laser pointer mounted on rod white index cards tape  
Telescope-based Optical Lever (see below):    
1 telescope monted on rod small lamp