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 | ||
B. | is smooth | ||
C. | has beads on it | ||
D. | has oil on it |
2. 1 pt(s). |
If the force from air friction on a rocket is made less, the highest speed it can go will | |
A. | be zero | |
B. | become lower | |
C. | stay the same | |
D. | become higher |
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 | ||
B. | be easier to clean | ||
C. | use more petrol every mile | ||
D. | be easier to stop |
4. 1 pt(s). |
The force of gravity pulling on an object is called its | |
A. | shape | |
B. | mass | |
C. | volume | |
D. | weight |
5. 1 pt(s). |
People in Australia do not fall off the Earth because | |
A. | the air pulls them down | |
B. | the Earth pulls them down | |
C. | the Earth is spinning around | |
D. | Australia is a large island |
6. 1 pt(s). |
The newton is a unit of | |
A. | charge | |
B. | volume | |
C. | weight | |
D. | frequency |
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 | ||
B. | B | ||
C. | C | ||
D. | D |
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 | ||
B. | B | ||
C. | C | ||
D. | D |
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 | ||
B. | bigger than on Y | ||
C. | less than on Y |
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 | ||
B. | bigger than before | ||
C. | less than before |
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 | ||
B. | decreases and it is more likely to skid | ||
C. | increases and it is less likely to skid | ||
D. | decreases and it is less likely to skid |
12. 1 pt(s). |
When energy is lost to friction, what is always made? | |
A. | heat | |
B. | a smell | |
C. | a noise | |
D. | light |
13. 1 pt(s). |
Which of the following will improve the streamlining of a car? | |
A. | Increasing the size of the engine in the car. | |
B. | Making the outside of the car a smooth shape. | |
C. | Increasing the weight of the car. | |
D. | Decreasing the weight of the car. | |
E. | Driving the car at high speeds. |
14. 1 pt(s). |
Two surfaces are in contact. Which of the following materials would reduce the friction between the surfaces? | |
A. | Sandpaper | |
B. | Rubber | |
C. | Concrete | |
D. | Oil | |
E. | Wood |
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? | |
A. | A cyclist oiling the chain of her bicycle | |
B. | An athlete wearing smooth, tight-fitting clothing | |
C. | A swimmer wearing a swimming cap | |
D. | A weightlifter chalking his hands | |
E. | A skier waxing her skis |