🔍 Key Concepts

• Basic parts of a ball bearing: inner race, outer race, balls, and cage • Which ring of a bearing is closest to the shaft and rotates with it • Difference between a race (rolling surface) and a cage (separator for the balls)

💭 Think About

• Look closely at where arrow A is pointing in relation to the central hole of the bearing. Would that part contact the shaft or the housing? • Which part of a bearing actually provides the running track for the balls on the inside versus the outside? • From the choices, which term describes a ring-shaped running surface, and which describes a part that spaces the balls apart?

✅ Before You Answer

• Confirm that the part at A is the innermost ring that would fit over a shaft, not the outer shell that fits the housing • Make sure you can distinguish between a race (smooth track the balls roll on) and a cage (retainer around the balls) • Eliminate any option that does not describe a ring-shaped running surface for the balls at the inside diameter