Topic 4 How rubbing makes a pull with no touch — what needs James (16)

Topic 4 · How rubbing makes a pull with no touch · Type 1 · tests FOR5-060

EasyMCQType 1 — what rubbing does to a thing; which action charges it

A plastic bag is rubbed on a wool blanket. What does the rubbing do to the bag?

1. a) It leaves the bag electrically charged. ← key
2. b) It makes the bag wet.
3. c) It makes the bag heavier.
4. d) It turns the bag into a magnet.

Why it is this type: Rubbing two things together can leave a thing electrically charged. The bag was rubbed on the wool blanket. So the rubbing left the bag electrically charged.

Recommendation: Approve as the exemplar

Topic 4 · How rubbing makes a pull with no touch · Type 2 · tests FOR5-060

EasyMCQType 2 — which word describes a described thing (charged, uncharged); which word says what it does (attracts)

A plastic bottle has stood on a shelf all week, and nothing has rubbed it. Which word describes the bottle?

1. a) electrically charged
2. b) uncharged ← key
3. c) a magnet
4. d) sticky

Recommendation: Approve as the exemplar

Topic 4 · How rubbing makes a pull with no touch · Type 3 · tests FOR5-060

EasyMCQType 3 — where the charge came from; what must be done to charge it; which of two things pulls thread; what left the fur charged; the reason only the rubbed bag pulls

A cotton cloth is rubbed on a plastic jar, and now the jar is electrically charged. Where did the charge on the jar come from?

1. a) The jar made it while it was being rubbed.
2. b) The rubbing moved it from the cloth onto the jar. ← key
3. c) It came from the air in the room.
4. d) It came up out of the table the jar stood on.

Recommendation: Approve as the exemplar

Topic 4 · How rubbing makes a pull with no touch · Type 4 · tests FOR5-061

EasyMCQType 4 — what the uncharged thing does near the charged thing (and near an unrubbed one); what the hanging charged thing does near an uncharged block; what a charged ruler pulls

A charged plastic bag is held near a cotton ball on a table, without touching it. What does the cotton ball do?

1. a) The cotton ball moves toward the bag. ← key
2. b) The cotton ball stays where it is.
3. c) The cotton ball moves away from the bag.
4. d) The cotton ball spins around.

Recommendation: Approve as the exemplar

Topic 4 · How rubbing makes a pull with no touch · Type 5 · tests FOR5-061

MediumMCQType 5 — when the foil starts to move; what tells you the bag is charged rather than sticky; the reason it pulls all three; what a charged ruler pulls, against a magnet

A charged plastic bag pulls a strip of newspaper toward it before they touch. Which of these tells you the bag is charged rather than sticky?

1. a) The bag is made of smooth plastic.
2. b) The strip is very thin and light.
3. c) The bag was rubbed on soft wool.
4. d) The bag pulls the strip from across a gap. ← key

Recommendation: Approve as the exemplar

Topic 4 · How rubbing makes a pull with no touch · Type 6 · tests FOR5-062

EasyMCQType 6 — what two charged things do (both rubbed the same way; a thing and the wool it was rubbed on; neither rubbed); which observation tells you they attract; what can happen

Two ribbons are both rubbed on the same wool blanket and hung side by side from threads. What do the ribbons do?

1. a) They attract.
2. b) They repel. ← key
3. c) They hang still.
4. d) They spin around.

Recommendation: Approve as the exemplar

Topic 4 · How rubbing makes a pull with no touch · Type 7 · tests FOR5-062

MediumMCQType 7 — the correct reason two strips spread apart

Two strips cut from a plastic bag, both rubbed on a wool sock, spread apart when held together by their tops. What is the correct reason?

1. a) The strips are too light to hang straight.
2. b) The air pushes the strips apart.
3. c) Only one of the strips is charged.
4. d) Both strips were rubbed the same way. ← key

Recommendation: Approve as the exemplar

Topic 4 · How rubbing makes a pull with no touch · Type 8 · tests FOR5-063

MediumMCQType 8 — which force moved the thing, nothing having touched it (a fall, a jump to a magnet, a jump to a charged bag, a hand's push)

A steel washer lies on a desk, and a magnet above it makes the washer jump up before they touch. Which force pulled the washer up?

1. a) its weight
2. b) the magnetic force ← key
3. c) a charged object's pull
4. d) a contact force

Recommendation: Approve as the exemplar

Topic 4 · How rubbing makes a pull with no touch · Type 9 · tests FOR5-063

HardMCQType 9 — which observation shows a force acting without touching; what is true of both forces; which things Earth pulls; a child's claim is wrong — the correct reason (the three register beliefs); two ideas chained (one strip near two things; which of two pulls the scrap; which force pulls down while the magnetic force pulls sideways)

Dorian says a magnet is the only thing that can move something without touching it. Dorian is wrong. What is the correct reason?

1. a) A magnet never pulls without touching.
2. b) Earth and a charged object also pull without touching. ← key
3. c) A magnet pulls only when it touches steel.
4. d) Only Earth pulls without touching.

Why it is this type: Hard because: the register's only-magnets belief is judged by its correct reason against two overstatements.

Recommendation: Approve as the exemplar

Topic 4 · How rubbing makes a pull with no touch · Type 10 · tests FOR5-063

HardtypedType 10 — the one word for what was done to the spoon; the word for what the bag does to the feather; the word for what two ribbons do; the word for what a ribbon and its wool do; the name of the force that pulled the bolt up; the name of Earth's pull on the raindrop

A raindrop falls from a cloud to the ground, and nothing touches it on the way down. Earth's pull on the raindrop has a name. Type the name of this force.

Accepted answers (typed): weight, its weight, the weight, weigth, wieght, its wieght, the raindrop's weight, raindrop's weight; "gravity" → "Gravity is the name for the happening, and the force is Earth's pull. Earth's pull on an object is called its weight."

Why it is this type: Hard because: the force's name is produced, and the student's own word, gravity, is the trap.

Recommendation: Approve as the exemplar

Topic 4 · How rubbing makes a pull with no touch · Type 11 · tests FOR5-063

Hardmulti-selectType 11 — the TWO forces that act without touching

Select the TWO forces in this list that can act without touching.

1. a) the magnetic force ← key
2. b) a contact force
3. c) an object's weight ← key
4. d) friction

Why it is this type: Hard because: a set is held together.

Recommendation: Approve as the exemplar