Lesson test: The world Copernicus inherited

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The world Copernicus inherited

1.[2p]
Why does Aristotle's physics require the heavens to be unchanging?

They are made of a fifth element whose only natural motion is uniform rotation, which has no beginning or end

Correct

Because no change had ever been recorded there

The answer is: They are made of a fifth element whose only natural motion is uniform rotation, which has no beginning or end

Because change would contradict scripture

The answer is: They are made of a fifth element whose only natural motion is uniform rotation, which has no beginning or end

Because the stars are too distant for change to be visible

The answer is: They are made of a fifth element whose only natural motion is uniform rotation, which has no beginning or end

2.[3p]
Match each piece of Ptolemy's machinery to what it does.

Deferent
Epicycle
Eccentric
Equant

the small circle whose centre rides the large one, producing retrogression
the large circle carrying the planet's motion around the earth
an offset of the large circle's centre from the earth
the third point about which the motion is uniform, which is what broke the physics

Show the answer

Deferent: the large circle carrying the planet's motion around the earth Epicycle: the small circle whose centre rides the large one, producing retrogression Eccentric: an offset of the large circle's centre from the earth Equant: the third point about which the motion is uniform, which is what broke the physics

3.[2p]
Name the device Copernicus objected to in his preface, the point about which motion is uniform.

CorrectNot quite: equant

4.[3p]
An astronomer can fix a star's position to 10 arcminutes and detects no parallax. What is the minimum distance to that star, in astronomical units?

CorrectNot quite: 344

5.[3p]
Why did the failure to detect stellar parallax get harder for Copernicans as instruments improved?

Better precision without a detection pushes the stars further out, making the empty gap more absurd

Correct

Better instruments detected a parallax in the wrong direction

The answer is: Better precision without a detection pushes the stars further out, making the empty gap more absurd

Better instruments were only used by opponents of Copernicus

The answer is: Better precision without a detection pushes the stars further out, making the empty gap more absurd

Precision made no difference, since parallax is unaffected by it

The answer is: Better precision without a detection pushes the stars further out, making the empty gap more absurd

6.[2p]
Ptolemy's lunar model puts the moon between about 33.5 and 64.2 earth radii, so it predicts that the moon's apparent diameter nearly doubles over a month.

True

Correct

False

The answer is: True

7.[2p]
The Julian year is 365.25 days and the tropical year is 365.2422 days. How many years does it take the calendar to drift by one whole day?

CorrectNot quite: 128

8.[3p]
Which of these were difficulties recognised from inside the earth-centred system before 1543?

Select all that apply

The equant broke the principle of uniform circular motion it was meant to serve

Correct

The lunar model got the moon's varying distance badly wrong

Correct

The Alfonsine Tables could be a month out on a conjunction

Correct

No stellar parallax could be detected

The answer is: The equant broke the principle of uniform circular motion it was meant to serve, The lunar model got the moon's varying distance badly wrong, The Alfonsine Tables could be a month out on a conjunction

9.[3p]
How was a disagreement in natural philosophy normally settled in 1500, and why was that reasonable?

By weighing authorities in a formal disputation, since no machinery existed for making one observer's report trustworthy

Correct

By experiment, which was already the standard method

The answer is: By weighing authorities in a formal disputation, since no machinery existed for making one observer's report trustworthy

By vote among the faculty of a university

The answer is: By weighing authorities in a formal disputation, since no machinery existed for making one observer's report trustworthy

By appeal to the pope, who ruled on questions about nature

The answer is: By weighing authorities in a formal disputation, since no machinery existed for making one observer's report trustworthy

1.[2p] Why does Aristotle's physics require the heavens to be unchanging?

2.[3p] Match each piece of Ptolemy's machinery to what it does.

3.[2p] Name the device Copernicus objected to in his preface, the point about which motion is uniform.

4.[3p] An astronomer can fix a star's position to 10 arcminutes and detects no parallax. What is the minimum distance to that star, in astronomical units?

5.[3p] Why did the failure to detect stellar parallax get harder for Copernicans as instruments improved?

6.[2p] Ptolemy's lunar model puts the moon between about 33.5 and 64.2 earth radii, so it predicts that the moon's apparent diameter nearly doubles over a month.

7.[2p] The Julian year is 365.25 days and the tropical year is 365.2422 days. How many years does it take the calendar to drift by one whole day?

8.[3p] Which of these were difficulties recognised from inside the earth-centred system before 1543?

9.[3p] How was a disagreement in natural philosophy normally settled in 1500, and why was that reasonable?

1.[2p]
Why does Aristotle's physics require the heavens to be unchanging?

2.[3p]
Match each piece of Ptolemy's machinery to what it does.

3.[2p]
Name the device Copernicus objected to in his preface, the point about which motion is uniform.

4.[3p]
An astronomer can fix a star's position to 10 arcminutes and detects no parallax. What is the minimum distance to that star, in astronomical units?

5.[3p]
Why did the failure to detect stellar parallax get harder for Copernicans as instruments improved?

6.[2p]
Ptolemy's lunar model puts the moon between about 33.5 and 64.2 earth radii, so it predicts that the moon's apparent diameter nearly doubles over a month.

7.[2p]
The Julian year is 365.25 days and the tropical year is 365.2422 days. How many years does it take the calendar to drift by one whole day?

8.[3p]
Which of these were difficulties recognised from inside the earth-centred system before 1543?

9.[3p]
How was a disagreement in natural philosophy normally settled in 1500, and why was that reasonable?