P5 Questions Flashcards
1
Q
water and water waves
A
Water particles move up + down
Water particles move 90 degrees to the direction of the wave
Energy moves in the direction of the wave
2
Q
How to measure speed of sound in air
A
- produce sound and receive by a receiver
- measure distance between source and microphone
- measure time between sound played on speaker and heard by receiver
- calc speed = d/t
- repeat + avg
3
Q
Ultrasound positives + negatives
A
Ultrasound show: - SOFT tissue, -kidneys, -blood flow - good for prenatal scans - Safe Ultrasound is only reflected by soft tissue - bone is not shown
4
Q
X-Rays positives + negatives
A
- show bone (absorbed by bone) = can save lives by identifying these problems
Damage, ionise living cells, can cause cancer + damage foetus
- high frequency but SMALL wavelengths to penetrate body