| 1. 1 pt(s). |
A girl puts her finger on the end of a syringe and pushes the plunger. The molecules in the air inside the syringe
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A. | get bigger | |
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B. | get smaller | |
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C. | move further apart | |
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D. | move closer together | |
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| 2. 1 pt(s). |
The two syringes in the diagram below are sealed, and then the plungers are squeezed. Plunger X moves in more than plunger Y, because
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A. | gas molecules are bigger than water molecules | |
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B. | water molecules are bigger than gas molecules | |
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C. | gas molecules are further apart than water molecules | |
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D. | water molecules are further apart than gas molecules | |
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| 3. 1 pt(s). |
Molecules in a liquid move | |
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A. | faster than in a gas |
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B. | faster than in a solid |
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C. | just as fast as in a gas |
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D. | just as fast as in asolid |
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| 4. 1 pt(s). |
Air pressure is caused by molecules which are | |
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A. | breaking up |
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B. | moving about |
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C. | getting bigger |
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D. | getting smaller |
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| 5. 1 pt(s). |
Look at the drawings of a rubber sucker. The sucker is pressed onto a wall. It stays stuck to the wall by itself because
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A. | rubber melts when squeezed | |
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B. | rubber becomes sticky when squeezed | |
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C. | air pressure holds it on the wall | |
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D. | small holes in the wall attract the sucker | |
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| 6. 1 pt(s). |
The syringe below is filled with cold air, and sealed. The length of X is 20mm. The syringe is dropped into boiling water. What could the length of X be now?
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A. | 9 mm | |
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B. | 15 mm | |
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C. | 19 mm | |
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D. | 25 mm | |
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| 7. 1 pt(s). |
When a metal expands its atoms | |
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A. | get smaller |
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B. | move more slowly |
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C. | move further apart |
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D. | move closer together |
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| 8. 1 pt(s). |
A bimetallic strip bends when heated because
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A. | the gas pushes it up | |
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B. | every metal bends when heated | |
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C. | one metal expands and the other contracts | |
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D. | one metal expands more than the other | |
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| 9. 1 pt(s). |
Look at the drawing below of a fire alarm. What is X?
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A. | copper rod | |
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B. | thermometer | |
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C. | bimetallic strip | |
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D. | slicon chip | |
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| 10. 1 pt(s). |
A blacksmith makes an iron tyre for a train wheel. The iron tyre is just too small to fit over the wheel. To make it fit over the wheel, the blacksmith | |
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A. | heats the tyre |
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B. | cools the tyre |
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C. | heats the wheel |
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D. | spins the wheel |
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| 11. 1 pt(s). |
Strips of copper and steel are joined together in the arrangements shown below. Copper expands more than steel. Which of the following will bend up when heated? | ||
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A. |
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B. |
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C. |
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D. |
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| 12. 1 pt(s). |
These bottles are full of air and are balanced on a nail. More air is then pumped into bottle X with a bicycle pump. Which drawing shows what happens?
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A. |
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B. |
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C. |
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D. |
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| 13. 1 pt(s). |
Examine the drawing below of a copper rod, which is 75.00mm long. The rod is heated strongly. How long could the rod now be?
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A. | 74.00mm | |
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B. | 74.80mm | |
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C. | 75.00mm | |
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D. | 76.00mm | |
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| 14. 1 pt(s). |
When all the air is sucked from an oil can, the can is crushed because | |
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A. | the air pressure outside is greater than that inside |
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B. | the air pressure inside is greater than that outside |
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C. | the heat has weakened the metal of the drum |
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D. | the ice has fractured the metal |
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| 15. 1 pt(s). |
When electricity wires are put up on pylons they are always left slack because they
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A. | use less cable | |
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B. | can carry more electricity | |
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C. | can expand safely in hot weather | |
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D. | can contract safely in cold weather | |
