1111 7777 3333 12 2222 8888 6666 9999 10. -5x = - 2y + 56 x = - 3y - 1 Home.
1111 2222 3333 4444 5555 6666 7777 8888 9999 10 11 12 13 14 15 16.
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Transcript of 1111 2222 3333 4444 5555 6666 7777 8888 9999 10 11 12 13 14 15 16.
![Page 1: 1111 2222 3333 4444 5555 6666 7777 8888 9999 10 11 12 13 14 15 16.](https://reader035.fdocuments.us/reader035/viewer/2022062216/56649c9d5503460f9495c39f/html5/thumbnails/1.jpg)
11 22 33 44 55 66 77
88 99 1010 1111 1212 1313 1414
1515 1616
![Page 2: 1111 2222 3333 4444 5555 6666 7777 8888 9999 10 11 12 13 14 15 16.](https://reader035.fdocuments.us/reader035/viewer/2022062216/56649c9d5503460f9495c39f/html5/thumbnails/2.jpg)
1. What is meant by the term: ultrasound
sound waves with a frequency above
20,000Hz
answer
![Page 3: 1111 2222 3333 4444 5555 6666 7777 8888 9999 10 11 12 13 14 15 16.](https://reader035.fdocuments.us/reader035/viewer/2022062216/56649c9d5503460f9495c39f/html5/thumbnails/3.jpg)
2. What is the speed of light in air?
300,000,000ms-1
answer
![Page 4: 1111 2222 3333 4444 5555 6666 7777 8888 9999 10 11 12 13 14 15 16.](https://reader035.fdocuments.us/reader035/viewer/2022062216/56649c9d5503460f9495c39f/html5/thumbnails/4.jpg)
3. A car has a parking sensor that emits ultrasound waves. They have a frequency of 40kHz ..Calculate their wavelength
answerm
f
v
3105.8
000,40
340
![Page 5: 1111 2222 3333 4444 5555 6666 7777 8888 9999 10 11 12 13 14 15 16.](https://reader035.fdocuments.us/reader035/viewer/2022062216/56649c9d5503460f9495c39f/html5/thumbnails/5.jpg)
4. A car stops 1.7m from a wall. Calculate the time for an ultrasound pulse from a parking sensor to reflect from the wall and return to the car.
answer
s
v
dt
01.0
340
4.3
![Page 6: 1111 2222 3333 4444 5555 6666 7777 8888 9999 10 11 12 13 14 15 16.](https://reader035.fdocuments.us/reader035/viewer/2022062216/56649c9d5503460f9495c39f/html5/thumbnails/6.jpg)
5. The car moves further from the wall, what happens to the time taken for the
Ultrasonic wave to return to the car?
The time will increase as it has further to travel
answer
![Page 7: 1111 2222 3333 4444 5555 6666 7777 8888 9999 10 11 12 13 14 15 16.](https://reader035.fdocuments.us/reader035/viewer/2022062216/56649c9d5503460f9495c39f/html5/thumbnails/7.jpg)
6. Why can we get a good radio signal in hilly areas but a poor TV signal?
Radio waves have a longer wavelength than TV waves and diffract more
answer
![Page 8: 1111 2222 3333 4444 5555 6666 7777 8888 9999 10 11 12 13 14 15 16.](https://reader035.fdocuments.us/reader035/viewer/2022062216/56649c9d5503460f9495c39f/html5/thumbnails/8.jpg)
7. What is meant by the frequency of a wave?
Number of complete waves that pass a point in
one second
answer
![Page 9: 1111 2222 3333 4444 5555 6666 7777 8888 9999 10 11 12 13 14 15 16.](https://reader035.fdocuments.us/reader035/viewer/2022062216/56649c9d5503460f9495c39f/html5/thumbnails/9.jpg)
8. Are light waves transverse or longitudinal waves?
Transverse
answer
![Page 10: 1111 2222 3333 4444 5555 6666 7777 8888 9999 10 11 12 13 14 15 16.](https://reader035.fdocuments.us/reader035/viewer/2022062216/56649c9d5503460f9495c39f/html5/thumbnails/10.jpg)
9.What is the frequency range of human hearing?
20Hz-20,000Hz
answer
![Page 11: 1111 2222 3333 4444 5555 6666 7777 8888 9999 10 11 12 13 14 15 16.](https://reader035.fdocuments.us/reader035/viewer/2022062216/56649c9d5503460f9495c39f/html5/thumbnails/11.jpg)
10. What is the threshold of pain for the human ears?
130dB
answer
![Page 12: 1111 2222 3333 4444 5555 6666 7777 8888 9999 10 11 12 13 14 15 16.](https://reader035.fdocuments.us/reader035/viewer/2022062216/56649c9d5503460f9495c39f/html5/thumbnails/12.jpg)
11. Give a use of ultrasound in medicine.
Scanning an unborn baby in the womb
answer
![Page 13: 1111 2222 3333 4444 5555 6666 7777 8888 9999 10 11 12 13 14 15 16.](https://reader035.fdocuments.us/reader035/viewer/2022062216/56649c9d5503460f9495c39f/html5/thumbnails/13.jpg)
12. True or false…Long wave are diffracted more than short waves?
TrueTrue
answer
![Page 14: 1111 2222 3333 4444 5555 6666 7777 8888 9999 10 11 12 13 14 15 16.](https://reader035.fdocuments.us/reader035/viewer/2022062216/56649c9d5503460f9495c39f/html5/thumbnails/14.jpg)
13. How could we protect our hearing from becoming damaged?
Wear ear muffs (ear protectors) that absorb
some of the sound energy.
answer
![Page 15: 1111 2222 3333 4444 5555 6666 7777 8888 9999 10 11 12 13 14 15 16.](https://reader035.fdocuments.us/reader035/viewer/2022062216/56649c9d5503460f9495c39f/html5/thumbnails/15.jpg)
14. Which sound has a higher pitch: a high frequency wave or a low frequency wave?
High frequencyHigh frequency
answer
![Page 16: 1111 2222 3333 4444 5555 6666 7777 8888 9999 10 11 12 13 14 15 16.](https://reader035.fdocuments.us/reader035/viewer/2022062216/56649c9d5503460f9495c39f/html5/thumbnails/16.jpg)
15. Why can sound not travel in a vacuum?
There are no air particles to carry the vibrations.
answer
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16. The frequency of a wave is 200Hz, Calculate the Period of this wave.
•.
answer
s
fT
005.0200
1
1