Electricity and safety

Tests: 4 of 11 right · Exam: 2 of 4 right · Kind: ★ · Understood: 8 of 15 · Run: 2026-10-18, commit f3c23ea72

Lesson 28 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 · ★ · right ✓

"Pure water is what makes electricity deadly," says a quiz show. Put it right.

1. Right, only pure water from a lab is ever dangerous — no support
2. Everyday water with salts in it carries electricity; very pure water hardly does — ← Mova's choice · ✓ the right answer · score 8
3. Wrong, no kind of water carries electricity — score 6
4. Right, salty water blocks electricity completely — score 6

Why: It took the question to ask which statement is true. It chose option 2 with score 8, against 6 for the next best. Its support: lesson 28, line 7: «It is a myth that only pure water is the danger: very pure water carries electricity poorly, but tap water, bath water and sweat carry it well.», reached through the option's own match among the sentences about the question's things. What matched: the same action «carry» (+3); the same thing acted on «electricity» (+3); the same doer «tap water» (+2). · the question and its options parsed, with trees and pragmatics

Test 2 · ★ · wrong ✗

mate says its fine in a storm in the car cos of the rubber tyres. true?

1. No, cars attract lightning straight inside to the people — ← Mova's choice · no support
2. No, a car is the worst place in a storm — no support
3. Safe, yes, but because of the metal body, not the tyres — ✓ the right answer · no support
4. Yes, rubber tyres stop any lightning — 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 ✓

Your little cousin is trying to push a hair clip into a socket. What should happen?

1. Stop her at once; a socket can give a deadly shock — ← Mova's choice · ✓ the right answer · no support
2. Let her, the shutters make it totally safe for children — no support
3. Turn off the lights first, then let her — no support
4. Let her, hair clips are too small to matter — 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 4 · ★ · wrong ✗

In a cartoon, a character dries her hair in the bath and nothing happens. What's wrong?

1. Nothing, because the bath water blocks electricity — ← Mova's choice · no support
2. The bath water would just get pleasantly warm, that's all — no support
3. Water carries electricity, so it could kill her — ✓ the right answer · no support
4. Hair dryers only ever blow out cold air near water — 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 5 · ★ · wrong ✗

Why can a bird sit on a wire, but a squirrel touching the wire and the pole at the same time gets a shock?

1. The squirrel makes a path to somewhere with a different push — ✓ the right answer · no support
2. The pole sucks electricity out of the wire — no support
3. Birds have rubber feet — score 0
4. Squirrels are made of metal inside — ← Mova's choice · score 1

Why: It took the question to ask why something happens (its cause). It chose option 4 with score 1, against 0 for the next best. Its support: lesson 28, line 3: «A bird can sit happily on a power line because it touches only one wire and nothing else, so the electricity has no reason to go through it; a person on a ladd…», reached through the cause of the sentence the question matched. What matched: the same doer «bird» (+2); a different action (counts against) (+1). Against it: a different thing acted on (counts against) (-2). The right option, 1, found no support in what it remembers. · the question and its options parsed, with trees and pragmatics

Test 6 · ★ · wrong ✗

shut up about the storm, I'm going out to fly my kite. good idea?

1. Yes, if the string is dry — ← Mova's choice · no support
2. No, but only because it might rain and spoil the nice kite — no support
3. No, stay inside; lightning and kites are a deadly mix — ✓ the right answer · no support
4. Yes, storms give the best wind — 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 · ★ · wrong ✗

Ali reckons electricity in your body is a myth. Is he right?

1. No, nerves and the heart use tiny electric signals — ✓ the right answer · no support
2. Yes, the human body runs only on chemicals and food — ← Mova's choice · score 5
3. No, our bodies are charged up like batteries all day — no support
4. Yes, only robots and machines can ever use electricity — score 4

Why: It took the question to ask which statement is true. It chose option 2 with score 5, against 4 for the next best. Its support: lesson 28, line 5: «Your own body runs on tiny electric signals too, far too weak to feel, which is why a strong shock from outside can upset your heart.», reached through the option's own match among the sentences about the question's things. What matched: the same action «run» (+3); the same doer «own body» (+2). The right option, 1, found no support in what it remembers. · the question and its options parsed, with trees and pragmatics

Test 8 · ★ · wrong ✗

What would happen if a metal kettle had a fault but no earth wire?

1. Nothing at all, because earth wires do nothing anyway — score 2
2. Touching it could send the electricity through you — ✓ the right answer · score 1
3. The kettle would boil water faster — no support
4. The water would turn into ice — ← Mova's choice · score 4

Why: It took the question to ask what happens next. It chose option 4 with score 4, against 2 for the next best. Its support: lesson 24, line 3: «In a kettle at 100 degrees, water turns into steam right inside the liquid and rises as big bubbles; the white cloud from the spout is tiny droplets of cooled…», reached through the option's own match among the sentences about the question's things. What matched: the same action «turn» (+2); the same doer «water» (+2). The right option, 2, scored 1. · the question and its options parsed, with trees and pragmatics

Test 9 · ★ · wrong ✗

Granddad is out in a field when thunder starts and there is no building nearby. What is best?

1. Run to the only tree in the field and shelter there — ← Mova's choice · no support
2. Lie down flat across the metal gate to keep off the grass — no support
3. Stand right on top of the hill to watch it coming in — no support
4. Stay low and away from tall things and open water — ✓ 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 10 · ★ · right ✓

Why might a large electric eel be dangerous to a person wading in a river?

1. It makes the water boil around you — no support
2. Its shock can be strong enough to knock a person over — ← Mova's choice · ✓ the right answer · score 3
3. It bites with electric teeth — no support
4. It sucks the electricity right out of the person's body — no support

Why: It took the question to ask why something happens (its cause). It chose option 2 with score 3, the only option with support. Its support: lesson 28, line 14: «An electric eel has special cells that work like hundreds of tiny batteries in a row, and a large eel can knock a person over.», reached through the option's own match among the sentences about the question's things. What matched: the same action «knock over» (+2); the same thing acted on «person» (+2). Against it: a different doer (counts against) (-1). · the question and its options parsed, with trees and pragmatics

Test 11 · ★ · right ✓

Mia's kite string touched a power line, and it's raining. Why is that worse?

1. Rain makes the power line switch off — no support
2. Rain turns the string into rubber — no support
3. A wet string carries electricity even more easily to the person — ← Mova's choice · ✓ the right answer · score 9
4. A wet kite floats away from the line — score 4

Why: It took the question to ask why something happens (its cause). It chose option 3 with score 9, against 4 for the next best. Its support: lesson 28, line 15: «A kite string, especially a wet one, can carry electricity from a power line to the person holding it.», reached through the option's own match among the sentences about the question's things. What matched: the same doer «kite string» (+3); the same action «carry» (+2); the same thing acted on «electricity» (+2); the same receiver «person» (+2). · the question and its options parsed, with trees and pragmatics

Exam question 1 · formal language · wrong ✗

Identify the principal reason for which no ordinary socket outlets are installed within bathrooms.

1. Socket outlets are incompatible with tiled surfaces — ← Mova's choice · no support
2. Water present in such rooms readily conducts electricity through the body — ✓ the right answer · no support
3. Electrical current would render the bath water toxic — no support
4. The humidity therein would exhaust the electrical supply — 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 2 · formal language · right ✓

Which of the following statements most accurately characterises the safety of a person within a motor vehicle during a thunderstorm?

1. The metallic body conducts any lightning around the occupants to earth — ← Mova's choice · ✓ the right answer · score 13
2. The vehicle affords no protection whatsoever — no support
3. The rubber tyres insulate the vehicle against all lightning — score 8
4. The glass windows deflect lightning away from the vehicle — no support

Why: It took the question to ask who or what does it. It chose option 1 with score 13, against 8 for the next best. Its support: lesson 28, line 12: «In a thunderstorm, the metal body of a car carries lightning round the people inside and into the ground; the tyres are not what protects them.», reached through the remembered sentence the question matched. What matched: it fills the role the question asks for (+6); the same doer «metal body» (+4); the same thing acted on «lightning» (+3). · the question and its options parsed, with trees and pragmatics

Exam question 3 · formal language · wrong ✗

Ascertain the reason for which a bird perched upon a single conductor sustains no injury.

1. Its plumage absorbs the entirety of the current flowing in the line — ← Mova's choice · no support
2. Birds are wholly immune to electric shock — no support
3. No path exists through its body to a point of differing potential — ✓ the right answer · no support
4. The current is suspended whenever a bird alights — 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 · right ✓

Select the response consistent with the established facts concerning the earth pin of a plug.

1. It affords stray current a safe path into the ground — ← Mova's choice · ✓ the right answer · score 7
2. It augments the power delivered to the appliance — no support
3. It serves solely to strengthen the plug mechanically — no support
4. It retains surplus electricity for later use — no support

Why: It took the question to ask which statement is true. It chose option 1 with score 7, the only option with support. Its support: lesson 28, line 17: «The thick earth pin on a plug gives stray electricity a safe path into the ground, so metal kettles and washing machines are earthed.», reached through the option's own match among the sentences about the question's things. What matched: the same action «give» (+3); the same doer «thick earth pin» (+2); the same place «ground» (+2). · the question and its options parsed, with trees and pragmatics

This page in Markdown → https://md.mova.elamur.ai/free/en/school-run/physics/28-electricity-and-safety/