Three Pith Balls Supported by Insulating Threads Hang from a Support

question 19

Multiple Choice

Three pith balls supported by insulating threads hang from a support. We know that ball X is positively charged. When ball X is brought near balls Y and Z without touching them, it attracts Y and repels Z. Since pith is an insulating material, we can conclude that

• A) Y has a negative charge.
• B) Z has a negative charge.
• C) Y has a positive charge.
• D) Z has a positive charge.
• E) Z is neutral (has no net charge.)

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Definitions:

Body Mechanics

The use of proper posture and movement in daily activities to prevent injury and maintain health.

Stretch Often

the recommendation to engage in regular stretching exercises to maintain flexibility and reduce the risk of injury.

Musculoskeletal Disorders

Conditions that affect the human body’s movement or musculoskeletal system, including muscles, bones, nerves, tendons, ligaments, and structures supporting the limbs, neck, and back.

Ergonomics

The study of people's efficiency in their working environment, focusing on the design of products and spaces to improve safety, comfort, and performance.