Which device is specifically used for lifting ferrous metals?

The device that is specifically used for lifting ferrous metals is an electromagnet. Electromagnets generate a magnetic field when electricity is passed through a coil of wire, allowing them to attract and hold ferrous metals, such as iron and steel. This capability makes electromagnets particularly useful in various industrial applications, including scrap metal handling and assembly lines where the lifting and transporting of ferrous materials is necessary.

Hydraulic jacks, forklifts, and pneumatic lifts can lift a variety of materials, but they do not have the specialized function of magnetically lifting ferrous metals. Hydraulic jacks rely on hydraulic fluid pressure, forklifts use forks to lift loads, and pneumatic lifts operate using compressed air. While these devices serve important roles in lifting and moving a wide range of materials, they do not have the specific attribute of magnetism that is inherent to electromagnets. Thus, the unique lifting capability of electromagnets for ferrous metals makes them the correct answer in this context.