Water safety and the ocean
Tests: 10 of 12 right · Exam: 1 of 4 right · Kind: ★★★ · Understood: 11 of 16 · Run: 2026-10-18, commit f3c23ea72
Lesson 13 of the physics 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 ✗
My mate reckons drowning people always scream and wave, so you'd know. right?
- 1. No, they often cannot shout or wave at all — ✓ the right answer · no support
- 2. Yes, they always scream for help — no support
- 3. No, they always swim fast — ← Mova's choice · score 4
- 4. Yes, and they always splash a lot so everyone sees — score 3
Why: It took the question to ask which statement is true. It chose option 3 with score 4, against 3 for the next best. Its support: lesson 11, line 17: «Muscle sinks more than fat, so very sporty people may float less well.», reached through the option's own match among the sentences about the question's things. What matched: the same action «float» (+2); the same doer «sporty people» (+2). The right option, 1, found no support in what it remembers. · the question and its options parsed, with trees and pragmatics
Test 2 · ★★★ · right ✓
the pond's frozen solid, dare ya to walk across. do it?
- 1. Yes, frozen means safe — no support
- 2. Yes, if you walk fast — no support
- 3. Yes, if you take off your shoes — no support
- 4. No, the ice can be too thin even if it looks solid — ← Mova's choice · ✓ the right answer · score 5
Why: It took the question to ask which statement is true. It chose option 4 with score 5, the only option with support. Its support: lesson 13, line 5: «Thick, very cold ice can carry a heavy lorry across a frozen lake in the far north, but ice on ponds at home can look solid and be far too thin, so never walk…», reached through a sentence linked to the one the question matched. What matched: the same doer «ice» (+3); the same property (+1); the same light verb (be, have, do, get, go) (+1). · the question and its options parsed, with trees and pragmatics
Test 3 · ★★★ · right ✓
You are caught in a rip current. Your friend says swim hard for the shore. What is better?
- 1. Stop moving and sink — no support
- 2. Dive under the water — no support
- 3. Swim sideways along the beach or float and wave — ← Mova's choice · ✓ the right answer · score 7
- 4. Swim even harder straight back — no support
Why: It took the question to ask which statement is true. It chose option 3 with score 7, the only option with support. Its support: lesson 13, line 14: «If a rip current pulls you out, swim sideways along the beach, not against it, or float and wave for help.», reached through the remembered sentence the question matched. What matched: the same place «beach» (+4); the same action «swim» (+3). · the question and its options parsed, with trees and pragmatics
Test 4 · ★★★ · right ✓
You see a kid in the deep end bobbing and gasping. What do you do?
- 1. Shout for the lifeguard at once — ← Mova's choice · ✓ the right answer · score 7
- 2. Laugh, because they are only playing a game — no support
- 3. Jump in and grab them yourself straight away — no support
- 4. Walk away and say nothing to anyone — no support
Why: It took the question to ask what is done. It chose option 1 with score 7, the only option with support. Its support: lesson 13, line 12: «If someone in the water looks wrong, call an adult or a lifeguard at once and never jump in after them yourself.», reached through the option's own match among the sentences about the question's things. What matched: it fills the role the question asks for (+3); the same action «call» (+2); the same circumstance (+2). · the question and its options parsed, with trees and pragmatics
Test 5 · ★★★ · right ✓
Your sister stands up in a canoe to wave. What will probably happen?
- 1. The canoe goes faster — no support
- 2. The canoe tips over — ← Mova's choice · ✓ the right answer · score 5
- 3. The canoe sinks slowly — no support
- 4. Nothing at all — no support
Why: It took the question to ask which statement is true. It chose option 2 with score 5, the only option with support. Its support: lesson 13, line 15: «A canoe tips over if someone stands up suddenly, because a boat is steady only while its weight is low, so keep low and in the middle.», reached through the same lesson line as the sentence the question matched. What matched: the same action «tip over» (+2); the same doer «canoe» (+2); the same property (+1). · the question and its options parsed, with trees and pragmatics
Test 6 · ★★★ · right ✓
What would happen to a diver who shot up from deep water very fast?
- 1. They could get badly hurt — ← Mova's choice · ✓ the right answer · no support
- 2. They would float forever — no support
- 3. They would get heavier — no support
- 4. Nothing, it is the safest way — 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 ✓
In a cartoon, a dam is built thin at the bottom and thick at the top. What is wrong?
- 1. The water presses hardest at the bottom — ← Mova's choice · ✓ the right answer · score 7
- 2. Nothing, because that is the right shape for a dam — no support
- 3. Water presses hardest at the top — score 7
- 4. Dams do not hold any water — no support
Why: It took the question to ask which statement is true. It chose option 1 with score 7, tied with another option at 7 (the first shown, or the one claiming less beyond what it knows, wins). Its support: lesson 13, line 10: «A dam is thick at the bottom because water presses harder the deeper it is.», reached through a sentence linked to the one the question matched. What matched: the same action «press» (+4); the same doer «water» (+3). · the question and its options parsed, with trees and pragmatics
Test 8 · ★★★ · wrong ✗
Your goldfish floats on its side. What might be wrong?
- 1. It has eaten far too much fish food — ← Mova's choice · no support
- 2. The water in the tank is too clean — no support
- 3. It is just having a nap on its side — no support
- 4. Its swim bladder may be sick — ✓ the right answer · 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 9 · ★★★ · right ✓
Why is polystyrene in the sea a problem?
- 1. It floats for years and pollutes the sea — ← Mova's choice · ✓ the right answer · score 5
- 2. It sinks and blocks the seabed — no support
- 3. It makes the waves bigger — no support
- 4. It melts in the sun and heats up the sea water — no support
Why: It took the question to ask why something happens (its cause). It chose option 1 with score 5, the only option with support. Its support: lesson 13, line 16: «Polystyrene, the light white foam used in packing, is mostly trapped air bubbles, so it floats almost on top of the water, and bits of it pollute the sea for y…», reached through the option's own match among the sentences about the question's things. What matched: the same action «float» (+3); the same doer «polystyrene» (+2). · the question and its options parsed, with trees and pragmatics
Test 10 · ★★★ · right ✓
Why can you easily lift a heavy friend in the pool but not on land?
- 1. Your arms get stronger in water — no support
- 2. Your friend breathes out all the air — no support
- 3. Wet skin is easier to grip — no support
- 4. Water holds up most of their weight — ← Mova's choice · ✓ the right answer · score 6
Why: It took the question to ask why something happens (its cause). It chose option 4 with score 6, the only option with support. Its support: lesson 13, line 18: «In a pool the water holds up most of your weight, because our bodies are about as heavy as water for their size, which makes swimming good for sore joints.», reached through the option's own match among the sentences about the question's things. What matched: the same action «hold up» (+3); the same doer «water» (+2); the same thing acted on «most» (+1). · the question and its options parsed, with trees and pragmatics
Test 11 · ★★★ · right ✓
Why can't people swim down to where the deepest fish live?
- 1. The water presses far too hard down there — ← Mova's choice · ✓ the right answer · score 5
- 2. It is far too dark down there to see where to swim — no support
- 3. The water is too salty — no support
- 4. The fish would chase them — no support
Why: It took the question to ask why something happens (its cause). It chose option 1 with score 5, the only option with support. Its support: lesson 13, line 8: «Deep-sea fish live under enormous pressure because their bodies are full of water, which hardly squashes and is pressed evenly from all sides.», reached through the same lesson line as the sentence the question matched. What matched: the same action «press» (+3); the same doer «water» (+2). · the question and its options parsed, with trees and pragmatics
Test 12 · ★★★ · right ✓
Why does a lorry not fall through the ice of a frozen northern lake?
- 1. The lorry has no weight on ice — no support
- 2. The water below holds the lorry — no support
- 3. The ice is thick and very cold — ← Mova's choice · ✓ the right answer · score 4
- 4. The lorry is driven very fast — no support
Why: It took the question to ask why something happens (its cause). It chose option 3 with score 4, the only option with support. Its support: lesson 13, line 5: «Thick, very cold ice can carry a heavy lorry across a frozen lake in the far north, but ice on ponds at home can look solid and be far too thin, so never walk…», reached through the option's own match among the sentences about the question's things. What matched: the same doer «thick cold ice» (+2); the same property (+2). · the question and its options parsed, with trees and pragmatics
Exam question 1 · formal language · wrong ✗
Which of the following statements most accurately characterises the pressure exerted by water at increasing depth?
- 1. It is exerted only upon the surface — no support
- 2. It increases with the depth of water above — ✓ the right answer · no support
- 3. It remains uniform at all depths — ← Mova's choice · score 3
- 4. It diminishes with the depth of water above — no support
Why: It took the question to ask who or what does it. It chose option 3 with score 3, the only option with support. Its support: lesson 13, line 17: «A goldfish stays at one depth by keeping just the right amount of gas in its swim bladder, and a fish floating on its side may have a sick swim bladder.», reached through the option's own match among the sentences about the question's things. What matched: the same action «stay» (+2); the same place «one depth» (+2). Against it: a different doer (counts against) (-1). The right option, 2, found no support in what it remembers. · the question and its options parsed, with trees and pragmatics
Exam question 2 · formal language · right ✓
Identify the conduct appropriate to a bather who is carried seawards by a rip current.
- 1. Swimming parallel to the shore, or floating and signalling for assistance — ← Mova's choice · ✓ the right answer · no support
- 2. Descending to the seabed until the current subsides — no support
- 3. Removing all clothing so as to diminish weight — no support
- 4. Swimming directly against the current with full exertion — 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
Exam question 3 · formal language · wrong ✗
It is given that a person in the water is observed to bob and gasp with the head inclined backwards. Ascertain the appropriate course of action for a child observer.
- 1. To enter the water and effect a rescue in person — ← Mova's choice · no support
- 2. To summon an adult or lifeguard without delay — ✓ the right answer · no support
- 3. To withdraw and inform no person — no support
- 4. To await further signals of distress — 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
Exam question 4 · formal language · wrong ✗
Determine the reason for which a dam is constructed with greater thickness at its base.
- 1. The upper portion of the dam bears the greatest pressure — ← Mova's choice · no support
- 2. Fish require a thick wall for shelter — no support
- 3. The pressure of the water increases with depth — ✓ the right answer · no support
- 4. The base must support a carriageway — 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
This page in Markdown → https://md.mova.elamur.ai/free/en/school-run/physics/13-water-safety-and-the-ocean/