Pendulums, Greenwich and railway time, atomic clocks and phones

Tests: 6 of 12 right · Exam: 0 of 4 right · Kind: ★ · Understood: 11 of 16 · Run: 2026-10-18, commit f3c23ea72

Lesson 123 of the world course of Mova's primary school, as Mova's small model took its tests: it had read this lesson and the ones before it and learned from their exercises. Each test shows the options in the order the student saw them, its choice, the right answer, the score of every option and why it chose. The lesson itself, sentence by sentence with trees and pragmatics: the lesson in the corpora.

Every question of this lesson and each of its options parsed by Mova, with trees and pragmatics: the lesson's questions in the corpora.

Test 1 · ★ · wrong ✗

Leo times a conker on a string: big swing, small swing, same time. His mate: "Nah, big swings take longer, deffo." Who's right?

1. Neither: a conker can't swing steadily — no support
2. Leo: Galileo found the swing time stays the same — ✓ the right answer · score 1
3. The mate: small swings take twice as long as big ones do — ← Mova's choice · score 5
4. The mate: big swings always take longer — score 5

Why: It took the question to ask which statement is true. It chose option 3 with score 5, tied with another option at 5 (the first shown, or the one claiming less beyond what it knows, wins). Its support: lesson 4, line 17: «The farther a planet is from the Sun, the longer it takes to go around it.», reached through the remembered sentence the question matched. What matched: the same action «take» (+4); the same property (+3). Against it: a different doer (counts against) (-2). The right option, 2, scored 1. · the question and its options parsed, with trees and pragmatics

Test 2 · ★ · wrong ✗

Ava: "15 minutes off a day down to 15 seconds, that's like sixty times better." Check her sum.

1. Wrong: it's 4 times better — ← Mova's choice · no support
2. Wrong: it's 900 times better — no support
3. Right: 900 seconds ÷ 15 = 60 — ✓ the right answer · no support
4. Wrong: it's only 15 times better — no support

Why: No option found support in what it remembers, so it guessed: it took the first option shown. · the question and its options parsed, with trees and pragmatics

Test 3 · ★ · right ✓

About Harrison's sea clock: "A clock that saves ships? Mint." ("Mint" means great.) How did a clock save ships?

1. It let sailors work out how far east or west they were — ← Mova's choice · ✓ the right answer · score 6
2. It steered the ship all by itself — no support
3. It warned sailors of storms coming by ringing a loud bell — no support
4. It kept the sailors awake at night — score 2

Why: It took the question to ask what something is like. It chose option 1 with score 6, against 2 for the next best. Its support: lesson 122, line 8: «A water clock lets water drip out at a steady speed, and the level falls past a mark for each hour; it works at night and on cloudy days.», reached through the option's own match among the sentences about the question's things. What matched: the same action «let» (+3); the same doer «water clock» (+2); a different thing acted on (counts against) (+1). · the question and its options parsed, with trees and pragmatics

Test 4 · ★ · right ✓

Mia's brother at Greenwich at 1 pm: "A ball drops down a pole. Is that it?!" Why did it matter?

1. It warned that the observatory was closing — no support
2. Ships on the Thames used it to set their clocks exactly — ← Mova's choice · ✓ the right answer · score 4
3. It was the signal for everyone in London to stop for lunch — no support
4. It told sailors the tide was coming in — no support

Why: It took the question to ask why something happens (its cause). It chose option 2 with score 4, the only option with support. Its support: lesson 123, line 12: «The red time ball at the Royal Observatory, Greenwich, has dropped at 1 pm every day since 1833 so ships could set their clocks.», reached through a sentence linked to the one the question matched. What matched: the same action «set» (+2); the same doer «ships» (+1); the same thing acted on «clocks» (+1). · the question and its options parsed, with trees and pragmatics

Test 5 · ★ · wrong ✗

Jake, from Birmingham: "Two minute hands on one clock, what's the point, bab?" ("Bab" means love or mate.) Why do they make sense?

1. One hand is for the left eye, one for the right — ← Mova's choice · no support
2. Before railways, each town kept its own Sun time — ✓ the right answer · no support
3. Bristol has two different hours in every day — no support
4. The clockmaker simply made a mistake — no support

Why: No option found support in what it remembers, so it guessed: it took the first option shown. · the question and its options parsed, with trees and pragmatics

Test 6 · ★ · right ✓

Lily: "So Greenwich is, like, the boss of time?" Best answer?

1. Greenwich is 0 degrees longitude, where time zones are counted from — ← Mova's choice · ✓ the right answer · no support
2. Greenwich has its own private time that nobody else in the world uses — no support
3. Greenwich decides what time everyone gets up — no support
4. Greenwich is where the first clock was ever made — no support

Why: No option found support in what it remembers, so it guessed: it took the first option shown. · the question and its options parsed, with trees and pragmatics

Test 7 · ★ · right ✓

Arjun: "A crystal in my watch wiggles? Dad's taking the mick." ("Taking the mick" means joking.) Is Dad joking?

1. No, a quartz crystal vibrates 32,768 times a second — ← Mova's choice · ✓ the right answer · score 3
2. No, but it only wiggles very slowly, about once a minute — no support
3. Yes, crystals are a kind of rock and can never move at all — no support
4. Yes, watches only ever use springs and little wheels — no support

Why: It took the question to ask which statement is true. It chose option 1 with score 3, the only option with support. Its support: lesson 123, line 4: «Today a quartz crystal in a watch wiggles 32,768 times a second, and atomic clocks count the "ticks" of caesium atoms so exactly they'd lose less than a second…», reached through the remembered sentence the question matched. What matched: the same property (+3); the same doer «quartz crystal» (+2). Against it: a different action (counts against) (-2). · the question and its options parsed, with trees and pragmatics

Test 8 · ★ · right ✓

Ollie: "Atomic clock? So it's never late for school, then." About how good are the best ones?

1. They lose about a second every single day of the year — score 6
2. They lose about one whole hour by the end of every year — no support
3. They lose about 15 seconds in a single day of ticking — score 6
4. They'd lose less than a second in millions of years — ← Mova's choice · ✓ the right answer · score 10

Why: It took the question to ask what something is like. It chose option 4 with score 10, against 6 for the next best. Its support: lesson 123, line 4: «Today a quartz crystal in a watch wiggles 32,768 times a second, and atomic clocks count the "ticks" of caesium atoms so exactly they'd lose less than a second…», reached through a sentence linked to the one the question matched. What matched: it fills the role the question asks for (+3); the same action «lose» (+2); the same thing acted on «less» (+2); the same place «millions» (+2). · the question and its options parsed, with trees and pragmatics

Test 9 · ★ · right ✓

Noah: "My phone knows the time and I never set it, lowkey creepy." ("Lowkey" means a bit.) How does it know?

1. It copies the time from the nearest phone — score 4
2. It gets the time from the network or GPS satellites with atomic clocks — ← Mova's choice · ✓ the right answer · score 9
3. It counts how many times you unlock it — no support
4. It reads where the Sun is in the sky by peeking through its camera lens all day — no support

Why: It took the question to ask what something is like. It chose option 2 with score 9, against 4 for the next best. Its support: lesson 123, line 18: «Phones get the time from the phone network or from GPS satellites, which carry atomic clocks.», reached through the option's own match among the sentences about the question's things. What matched: the same place «phone network» (+4); the same doer «phones» (+2); it fills the role the question asks for (+2); the same light verb (be, have, do, get, go) (+1). · the question and its options parsed, with trees and pragmatics

Test 10 · ★ · wrong ✗

Nan: "We dialled 123 for the speaking clock, love." Mila: "The what?" What was it?

1. A talking alarm clock sold in shops — score 6
2. A radio show about old clocks — ← Mova's choice · score 11
3. A clock that answered questions out loud — no support
4. A phone number where a voice said the exact time — ✓ the right answer · no support

Why: It took the question to ask what it is done to. It chose option 2 with score 11, against 6 for the next best. Its support: lesson 123, line 13: «Bristol is about 10 minutes behind London by the Sun; its Corn Exchange clock has two minute hands to show both times.», reached through the remembered sentence the question matched. What matched: the same circumstance (+7); the same action «show» (+2); a different doer (counts against) (+2). The right option, 4, found no support in what it remembers. · the question and its options parsed, with trees and pragmatics

Test 11 · ★ · wrong ✗

What would happen if you took an ordinary pendulum clock onto a rolling ship?

1. The rocking would upset the swing and it would keep bad time — ✓ the right answer · score 3
2. It would turn into a proper sea clock all by itself after a while — score 3
3. It would keep even better time, thanks to the rocking of the waves — score 3
4. It would work exactly as it does on land, with no change at all — ← Mova's choice · score 4

Why: It took the question to ask what happens next. It chose option 4 with score 4, against 3 for the next best. Its support: lesson 122, line 8: «A water clock lets water drip out at a steady speed, and the level falls past a mark for each hour; it works at night and on cloudy days.», reached through the option's own match among the sentences about the question's things. What matched: the same action «work» (+3); the same doer «clock» (+1). The right option, 1, scored 3. · the question and its options parsed, with trees and pragmatics

Test 12 · ★ · wrong ✗

Grandad: "The pips! Six beeps, set your watch on the first one." Fix his mistake.

1. The pips have nothing to do with the hour — ← Mova's choice · score 1
2. The first pip marks the start of the hour — score 1
3. The last pip marks the exact start of the hour — ✓ the right answer · score 1
4. The third pip marks the start of the hour — score 1

Why: It took the question to ask which statement is true. It chose option 1 with score 1, tied with another option at 1 (the first shown, or the one claiming less beyond what it knows, wins). Its support: lesson 123, line 19: «Britain's speaking clock (dial 123) began in 1936, and the BBC's six "pips" have marked the hour since 1924; the last pip marks the exact start of the hour.», reached through the option's own match among the sentences about the question's things. What matched: the same property (+1). The right option, 3, scored 1. · the question and its options parsed, with trees and pragmatics

Exam question 1 · formal language · wrong ✗

Identify the property of the pendulum observed by Galileo.

1. The period of a swing is the same whether the swing be large or small — ✓ the right answer · no support
2. A pendulum ceases to swing after one minute — ← Mova's choice · score 1
3. A pendulum swings more rapidly in the evening — score 1
4. The period of a swing doubles whenever the swing becomes twice as large — no support

Why: It took the question to ask which statement is true. It chose option 2 with score 1, tied with another option at 1 (the first shown, or the one claiming less beyond what it knows, wins). Its support: lesson 123, line 8: «A pendulum about 1 metre long takes about 1 second to swing one way.», reached through the option's own match among the sentences about the question's things. What matched: the same action «swing» (+1). The right option, 1, found no support in what it remembers. · the question and its options parsed, with trees and pragmatics

Exam question 2 · formal language · wrong ✗

Given that a navigator's clock indicates two o'clock in the afternoon, London time, at the moment of local noon, and that the Earth rotates fifteen degrees per hour, ascertain the position of the ship.

1. Thirty degrees east of Greenwich — no support
2. Two degrees west of Greenwich — ← Mova's choice · score 3
3. Thirty degrees west of Greenwich — ✓ the right answer · score 3
4. Fifteen degrees west of Greenwich — score 3

Why: It took the question to ask which statement is true. It chose option 2 with score 3, tied with another option at 3 (the first shown, or the one claiming less beyond what it knows, wins). Its support: lesson 123, line 2: «A clock can even tell you where you are. The Earth turns 15 degrees an hour, so if your clock still shows London time and the Sun is highest at 2 pm, you are 3…», reached through the same lesson line as the sentence the question matched. What matched: the same thing acted on «30 degrees» (+2); the same property (+1). The right option, 3, scored 3. · the question and its options parsed, with trees and pragmatics

Exam question 3 · formal language · wrong ✗

Select the response consistent with the established facts concerning the international conference of 1884.

1. Summer time was adopted throughout Europe — ← Mova's choice · no support
2. The first atomic clock was demonstrated — no support
3. Greenwich was adopted as the meridian of zero degrees longitude — ✓ the right answer · no support
4. Paris was adopted as the meridian of zero degrees longitude — no support

Why: Nothing it remembers matched the question, so it guessed: it took the first option shown. · the question and its options parsed, with trees and pragmatics

Exam question 4 · formal language · wrong ✗

Which of the following statements most accurately characterises the means whereby a mobile telephone ascertains the time?

1. It derives the time from the position of the Sun — ← Mova's choice · no support
2. It receives signals from the network or from satellites carrying atomic clocks — ✓ the right answer · no support
3. It relies exclusively on manual setting by its owner — no support
4. It measures the swings of an internal pendulum — no support

Why: No option found support in what it remembers, so it guessed: it took the first option shown. · the question and its options parsed, with trees and pragmatics

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