In which of the following devices, the eddy current effect is not used?

Eddy currents are induced circulating currents in conductors when exposed to changing magnetic fields.Induction furnace: Uses eddy currents to produce high heat to melt metals.Magnetic braking: Uses eddy currents to create a dragging force that slows down the train.Electromagnet: Can use eddy current effects for damping or core stabilization, though primary function is field generation.Electric heater: Works on the principle of Joule heating ($H=I^{2}Rt$) through a high-resistance coil (like Nichrome), not via electromagnetic induction or eddy currents.