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Technology: Engineering Our World
Reducing Friction
Friction may be reduced in several ways, as shown in Figure 8-60
through Figure 8-62.
• Ball bearings—steel balls enable surfaces to roll over one another
instead of sliding.
• Air or water cushions—compressed air or water separates moving
parts.
• Streamlining—the shape of a fast-moving object can be changed to
reduce its resistance to air or water.
Rotary to linear Rotary to reciprocating
Rotary to linear Reciprocating to rotary
gure 8-59. Mechanisms change
motion from one form to another.
A
Ball bearings
B
gure 8-60. A—Ball bearings allow parts to roll over one another, reducing friction. B—The
bearings in this shaft are separated to provide more structural stability to the product.