Year 9 Physics 2015 Name: Yhanie Blase Date: 19/08/15
Q Marks
1 2 What is an echo? Explain why an empty room will produce one? [2 marks]
Echo is a sound(s) caused by the reflection of sound waves from a surface back to the listener. An empty room will produce an echo because the sound can bounce freely back to the source. When the sound waves bounce, they will can bounce right back to the source because there’s no blocking their way. However, when there is furniture, the sound waves will bounce back everywhere but back to the source, hence, little to no echo.
2 5 Explain how sonar works and why it is useful. Provide at least one diagram or picture. [5 marks]
Sonar uses sound waves or echoes to locate something underwater. It’s useful
…show more content…
The transmitted pulses are reflected by the target and then received by the same radar. The reflected energy or the echoes are further processed to extract target information.
4 5 Explain how ultrasound works and why it is useful. Provide at least 2 examples of its use today. [5 marks]
Ultrasound is a medical imaging technique that uses high frequency sound waves and their echoes. It is useful because it can help show if there is a problem with you blood circulation in a limb or your heart or if you are pregnant. Ultrasound can help check on the developing baby or determine the due date. Ultrasound also helps you look at your blood flow (Doppler Ultrasound).
5 3 Describe ONE of the following: Sonagraph, 3D ultrasound, Doppler ultrasound [3 marks]
Doppler Ultrasound is a special ultrasound technique that allows the physician to see and evaluate blood flow through arteries and veins in the abdomen, arms, legs, neck and/or brain (in infants and children) or within various body organs such as the liver or kidneys.
3 types of Doppler Ultrasound:
- Colour Doppler
- Power Doppler
- Spectral Doppler
5 Bibliography: (source for each question)
To be typed up and submitted via connect.
Total score / 25 %