Basic Waves 2

Question 1

Soundwaves are caused by oscillating particles
in the medium. This causes areas of
compression (——————-) and rarefaction
(——————-). The oscillations of particles
are —————— to the direction of energy transfer.

Answer 1

High pressure, Low pressure, parallel.

Question 2

Sound can move through —— and ——
but most commonly we look at sound moving
in —-.

Answer 2

Solids, liquids, air

Question 3

Human hearing can has a frequency range from —- to —- hz.

Answer 3

20 Hz to 20000 Hz

Question 4

Infra sound is sound with a frequency —— humanhearing

Answer 4

below

Question 5

Ultrasound is sound with a frequency —- human hearing

Answer 5

above

Question 6

Examples of Infrasound?

Answer 6

Some animals, such as whales, elephants and giraffes communicate using infrasound over long distances.

Question 7

Example of Ultrasound?

Answer 7

Some animals, such as bats communicate using ultrasound. We can also use it for medial imaging.

Question 8

Bats use an —— system. They make high frequency sound —— which last about 3ms. When the sound hits a nearby object, it is reflected back.

Answer 8

echo location, Pulses

Question 9

It takes time for the sound to reach the object then —— back. The nearer the object the —- time it will take.

Answer 9

reflect, less

Question 10

The signal must be in —— rather than —— as the time it takes for the echo to return needs to be measured.

Answer 10

pulses, continuous

Question 11

The pulse must return —— the next one is sent.

Answer 11

before

Question 12

If it was —— you couldn’t tell when the signal arrived back.

Answer 12

continuous

Question 13

The —— the pulse the —— the distance that can be measured.

Answer 13

shorter, shorter

Question 14

Humans use machines to do the same job; for working out —— to objects.

Answer 14

distance

Question 15

This is especially useful in where?

Answer 15

places where it is hard to see.

Question 16

By timing how long it takes for the signal to come back we can work out the distance to the object using?

Answer 16

𝐷𝑖𝑠𝑡𝑎𝑛𝑐𝑒 = 𝑆𝑝𝑒𝑒𝑑 × 𝑡𝑖𝑚𝑒

Question 17

Sonar can be used —— to measure distance between objects.

Answer 17

underwater

Question 18

Pulse echo measurements can also be used to ——.
This works because then sound will reflect of any——.

Answer 18

Create an image, Boundary

Question 19

A computer can build an image from all ———.

Answer 19

the echo measurements

Question 20

Pulse echos don’t have to be sound.
Radar uses —— waves to detect where planes are in the sky. These travel much —— so the pulses can be shorter and the distances longer.

Answer 20

Radio, faster