Wab=qu=q(ψa-ψb),因为ψb=0,所以Wab=qψa,即-3×10-5J=-6×10-6C*ψa,ψa=5v.
Wbc=q(ψb-ψc),即1.2×10-5J=-6×10-6C*(0-ψc),ψc=2v.
即:ψa=5v ψc=2v