Question

by the late 19th century, the rayleigh - jeans law predicted that a blackbody object would emit infinite energy at ultraviolet wavelengths, a theoretical absurdity known as the \ultraviolet catastrophe.\ to resolve this paradox, physicist max planck introduced a radical ansatz in 1900: he proposed that electromagnetic energy could only be emitted in discrete packets, or \quanta.\ however, planck initially characterized this quantization as a mere mathematical device designed to stabilize his equations, rather than a discovery about the intrinsic nature of light. it was only later that albert einstein would demonstrate that these quanta were physically real, transforming planck’s reluctant calculation into the bedrock of a new scientific era.

which choice best describes the function of the underlined sentence in the text as a whole?
(answer : d)
a it distinguishes between planck’s use of a specific computational concept and his acceptance of its physical reality, underscoring his visionary foresight regarding his own innovation.
b it emphasizes that planck did not recognize the broader physical implications of his quantization concept, setting up the comparison with einstein’s subsequent demonstration of this perspective.
c it describes the significance planck attributed to his innovation, indicating he saw it as a fundamental truth going beyond a pragmatic fix, a view the passage notes einstein would later challenge.
d it clarifies that planck viewed his innovation as a computational tool rather than a physical truth, highlighting a cautious stance that einstein would later overturn.

Explanation:

To determine the function of the underlined sentence, we analyze its content and context:

1. The underlined sentence states that Planck initially saw his quantization as a "mathematical device" (a computational tool) rather than a discovery about the "intrinsic nature of light" (physical truth).
2. Later, Einstein demonstrated the physical reality of quanta, overturning Planck's initial view.
3. Option A is incorrect because the sentence does not discuss Planck's acceptance of physical reality.
4. Option B is incorrect as the sentence does not emphasize Planck's lack of recognition of broader implications but rather his view of quantization as a mathematical tool.
5. Option C is incorrect because the sentence shows Planck did not see his innovation as a fundamental truth.
6. Option D matches: it clarifies Planck viewed his innovation as a computational tool (not physical truth) and highlights that Einstein later overturned this cautious stance (by showing quanta were real).

Answer:

D. It clarifies that Planck viewed his innovation as a computational tool rather than a physical truth, highlighting a cautious stance that Einstein would later overturn.