| 1. 1 pt(s). |
A boy pulls a box across a a table. The friction will be biggest if the table
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A. | is rough | |
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B. | is smooth | |
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C. | has beads on it | |
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D. | has oil on it | |
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| 2. 1 pt(s). |
If the force from air friction on a rocket is made less, the highest speed it can go will | |
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A. | be zero |
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B. | become lower |
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C. | stay the same |
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D. | become higher |
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| 3. 1 pt(s). |
A car mechanic changed the brakes on a car, so that there was no friction between the brakes and the wheels. The car will
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A. | be harder to stop | |
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B. | be easier to clean | |
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C. | use more petrol every mile | |
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D. | be easier to stop | |
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| 4. 1 pt(s). |
The force of gravity pulling on an object is called its | |
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A. | shape |
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B. | mass |
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C. | volume |
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D. | weight |
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| 5. 1 pt(s). |
People in Australia do not fall off the Earth because | |
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A. | the air pulls them down |
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B. | the Earth pulls them down |
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C. | the Earth is spinning around |
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D. | Australia is a large island |
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| 6. 1 pt(s). |
The newton is a unit of | |
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A. | charge |
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B. | volume |
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C. | weight |
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D. | frequency |
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| 7. 1 pt(s). |
Examine the diagrams of test tubes below. There is a bead in each tube. The tubes were turned over at the same time. In which test tube will friction be greatest
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A. | A | |
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B. | B | |
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C. | C | |
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D. | D | |
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| 8. 1 pt(s). |
Examine the diagrams of test tubes. There is a bead in each tube. The tubes were turned over at the same time. In which test tube will the bead reach the bottom first?
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A. | A | |
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B. | B | |
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C. | C | |
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D. | D | |
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| 9. 1 pt(s). |
In the experiment shown in the diagram, the boxes are given the same push. they slide across the table. Box X stops first. The friction on X is
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A. | the same as on Y | |
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B. | bigger than on Y | |
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C. | less than on Y | |
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| 10. 1 pt(s). |
The hinges on a door are oiled. When the door is moved, the friction in the hinges is
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A. | the same as before | |
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B. | bigger than before | |
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C. | less than before | |
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| 11. 1 pt(s). |
After it has rained, the friction between car tyre and the road
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A. | increases and it is more likely to skid | |
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B. | decreases and it is more likely to skid | |
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C. | increases and it is less likely to skid | |
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D. | decreases and it is less likely to skid | |
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| 12. 1 pt(s). |
When energy is lost to friction, what is always made? | |
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A. | heat |
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B. | a smell |
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C. | a noise |
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D. | light |
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| 13. 1 pt(s). |
Which of the following will improve the streamlining of a car? | |
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A. | Increasing the size of the engine in the car. |
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B. | Making the outside of the car a smooth shape. |
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C. | Increasing the weight of the car. |
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D. | Decreasing the weight of the car. |
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E. | Driving the car at high speeds. |
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| 14. 1 pt(s). |
Two surfaces are in contact. Which of the following materials would reduce the friction between the surfaces? | |
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A. | Sandpaper |
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B. | Rubber |
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C. | Concrete |
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D. | Oil |
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E. | Wood |
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| 15. 1 pt(s). |
Sportsmen and sportswomen use a variety of methods to increase or decrease the force of friction. Which of the following statements describes a method used to increase the force of friction? | |
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A. | A cyclist oiling the chain of her bicycle |
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B. | An athlete wearing smooth, tight-fitting clothing |
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C. | A swimmer wearing a swimming cap |
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D. | A weightlifter chalking his hands |
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E. | A skier waxing her skis |
