Two Small Insulating Spheres Are Attached to Silk Threads and Aligned

question 39

Multiple Choice

Two small insulating spheres are attached to silk threads and aligned vertically as shown in the figure. These spheres have equal masses of 40 g, and carry charges q1 and q2 of equal magnitude 2.0 μC but opposite sign. The spheres are brought into the positions shown in the figure, with a vertical separation of 15 cm between them. Note that you cannot neglect gravity. (k = 1/4πε0 = 8.99 × 10⁹ N ∙ m²/C²) The tension in the lower thread is closest to

• A) 1.2 N.
• B) 1.4 N.
• C) 1.6 N.
• D) 1.8 N.
• E) 2.0 N.

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Definitions:

Intellectual Development

The development of cognitive abilities and intellectual capacities, including thinking, problem-solving, and understanding concepts.

Cross-sequential

A research method that combines both cross-sectional and longitudinal designs to study changes over time in a faster and more efficient manner.

Successive Cohort

Groups of individuals born in consecutive chronological segments, often studied to observe changes over time in a particular population.

Spatial Orientation

The ability to recognize and navigate the position and direction of oneself and objects in space.