What is the primary function of a gearbox in a drive system?

• A. To convert electrical energy to mechanical energy
• B. To change speed and torque by providing a designated gear reduction or multiplication
• C. To absorb vibrations
• D. To provide electrical isolation

Answer: (C)

The main idea is that a gearbox changes how the motor’s power is delivered by using gear ratios to alter speed and torque. By selecting gears of different sizes, you reduce or increase speed and, correspondingly, increase or decrease torque to match what the driven machine needs. This speed-torque transformation is what makes the system able to start, accelerate, and run at the desired RPM efficiently. Absorbing vibrations is not the primary role of a gearbox; while gear design and mounting can influence vibration indirectly, damping is more the job of dampers or isolation components. A gearbox doesn’t convert electrical energy to mechanical energy (that’s the motor’s job) or provide electrical isolation.