Reading Comprehension

PT115 · S3 · P3 · Q20 Planck and Wave Theory

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With the approach of the twentieth century, the classical wave theory of radiation—a widely accepted theory in physics—began to encounter obstacles.

Topic

Wave theory of radiation

Framework

old / new

Paragraph 1 The very first sentence warns us that we're probably reading an Old/New type passage (along with the fact that Old/New is the most common framework for Science) passages.

An accepted theory is encountering obstacles?

When you suspect an Old/New framework, you try to proactively predict the New, by defining it as the logical opposite of the Old (in the hopes of priming your brain so that it's easier to process the payoff sentences when they arise).

Old New all EM radiation exists some EM radiation in the form of waves isn't in wave form?

as length of wave as length of wave shortens, its energy shortens, its energy increases smoothly doesn't go up like (volume dial) a smooth volume dial?

Any conceivable some energy values energy value could can't occur in occur in nature nature?

Paragraph 2 The transition sentence warns us that we're about to hear the story of the "obstacles" that wave theory started to encounter. Many science passages with an Old/New structure have a section where they're saying: Scientists thought / assumed X, which meant that Y should be true. But then data showed that Y wasn't true!

This happens when we hear that physicists originally predicted they would find more energy at short wavelengths, however they found almost none.

This tension is what sets us up for the New.

Paragraph 3 The second sentence gives us Planck's answer to this conundrum -- "get rid of the Old volume dial / continuous view of energy, start using a New incremental-click / discontinuous view".

We even get a mini Old/New at the end of the paragraph as we learn that "at first" the physics community was deeply reluctant to accept this, since Planck had no physical explanation to back this up.

Paragraph 4 This paragraph opens with a continuator that says Einstein and others came to the rescue by coming up with a different theory of energy that could explain why Planck's incremental-click / discontinuous view could be legit.

The big breakthrough here was the idea of positing particles (photons) that are discrete units and certain wavelengths. (a particle is a quantum of energy, a specific quantity of energy ... which is where the name quantum physics comes from )

20.

The author's attitude toward Planck's development of a new hypothesis about atomic processes can most aptly be described as

  1. strong admiration for the intuitive

    Contradicted

    Since we know this knew theory goes directly against wave theory's conception of atomic processes, it makes no sense to say that this led to restored confidence in wave theory.

    8% picked this

  2. mild surprise at the bizarre

    Unsupported: surprise

    This answer is tough to get rid of, since "mild surprise" is, well, so mild. The problem is that we don't have any explicit text indicating that our author is surprised. She is just describing that Planck's contemporaries would have been surprised, since it was a then-bizarre position. The author's descriptions in the 3rd paragraph are all pretty neutral and objective. - Max developed a hypothesis that broke with wave theory and accounted for the weird data. - He discarded an old assumption and took the then bizarre position, and he thereby obtained numbers that perfectly fit the earlier result. - This directly opposed wave theory and the physics community was at first quite critical. If we didn't have a "more apt" answer like (E), then we could probably live with this, but the author's attitude is pretty invisible, and "mild surprise" needs something visible to touch on.

    10% picked this

  3. reasoned skepticism of Planck’s lack

    Unsupported: skepticism

    This is similar to (B). The author described a surprising position P took, but that doesn't mean the author was mildly surprised. Here, the author is describing the physics community's skepticism of P's controversial theory (especially since P didn't have much to support it). But that doesn't mean the author was being skeptical of Planck. These are tough, though, since "mild surprise" and "reasoned skepticism" are so gently worded they could almost be invisible attitudes. But they can't be totally invisible. And they are. We can't point to where the author sounds surprised or where the author sounds skeptical, just to sentences where she is describing other people being surprised and skeptical.

    5% picked this

  4. legitimate concern that the hypothesis

    Unsupported: concern Too Strong: abandoned

    We can't really find any wording to point to that sounds like the author is worried the theory would be totally discarded (abandoned). The author is just saying that the theory wasn't initially embraced, but that doesn't mean it would have been totally shunned. Scientific theories can definitely persist for a long time in indefinite states. This answer would be pulling its best support from the end of P3 and beginning of P4. The disconnect would be analogous to this: paragraph: At first, when Todd arrived at Amy's party, he wasn't having fun. Soon thereafter, though, Einstein showed up with his hookah and he was happier. answer: The author is worried that Todd would have had a terrible time if it weren't for Einstein and his hookah. This sounds like an amplification of the first statement, not a regurgitation. Einstein was sufficient for saving the party / supporting Planck. But he wasn't necessary. Something else might have happened to perk up Todd / support Planck's new vision.

    4% picked this

  5. Correct

    scholarly interest in a step

    Why this is right

    This is actually one of the only correct answers I've ever seen on an attitude question that was "neutral". The tone of this passage overall is explanatory and descriptive. We don't hear any clashes of opinions between the author and other points of view. The author doesn't have any opinion, other than a consistent sense of interest in this story. It's clear she thinks this is an interesting story that has importance. If you note, every single verb in the passage is past tense. It's telling a historical story, with a minimum of tone to emphasize the drama of the story. The last sentence probably sparkles with the most attitude, "in just a few years, what was considered a catastrophe generated a new vision in physics". Since Planck's theory of atomic processes is being told to us through the lens of someone telling us the story of his victorious new vision, we would expect the writer's attitude to sound affirming and appreciative of Planck's contribution.

    Skill tested: Author's Attitude · how this choice captures the passage's function is the move to repeat next time.

    73% picked this

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