Rack and pinion are employed when it is necessary to change

Rack and pinion are employed when it is necessary to change

• A. Variable speed to constant speed
• B. Circular motion to cam motion
• C. Cam motion to circular motion
• D. Circular motion to linear motion

Answer: (D)

Rack and pinion change circular motion into linear motion. The pinion is a gear that rotates, and its teeth mesh with a straight rack. As the pinion turns, the rack slides in a straight line, translating rotational input into linear output. This is why it’s used in places where you need straight-line movement derived from rotation, such as steering a vehicle, where turning the wheel rotates the pinion and moves the rack to steer the wheels. It isn’t about converting speeds, nor about turning circular motion into cam motion or vice versa; the mechanism specifically converts rotation to straight-line motion.

Rack and pinion change circular motion into linear motion. The pinion is a gear that rotates, and its teeth mesh with a straight rack. As the pinion turns, the rack slides in a straight line, translating rotational input into linear output. This is why it’s used in places where you need straight-line movement derived from rotation, such as steering a vehicle, where turning the wheel rotates the pinion and moves the rack to steer the wheels. It isn’t about converting speeds, nor about turning circular motion into cam motion or vice versa; the mechanism specifically converts rotation to straight-line motion.