Waves

Question 1

What is a transverse wave?

Answer 1

A wave in which the medium vibrates at right angles to the direction of the wave.

Question 2

What is a longitudinal wave?

Answer 2

A wave in which the medium vibrates back and forth in the same direction as the wave.

Question 3

What are examples of a transverse wave?

Answer 3

Electromagnetic waves (light waves), water waves, guitar string vibrations

Question 4

What are examples of longitudinal waves?

Answer 4

Sound waves, slinkies, earthquakes

Question 5

What is the speed of sound in air?

Answer 5

340m/s

Question 6

What is the speed of light in air?

Answer 6

3 x 10(8) m/s

Question 7

What is wavelength?

Answer 7

The distance between two adjacent identical parts of a wave (i.e. two peaks or two troughs)

Question 8

What is the formula for distance, speed and time?

Answer 8

d (distance) units: m (metres)
v (speed/velocity) units: m/s (metres per second)
t (time) units: s (seconds)

Question 9

What is a period?

Answer 9

The amount of time it takes for one cycle (wavelength) to pass by.

Question 10

What is frequency?

Answer 10

How many wavelengths pass by in one second.

Question 11

What is the formula for frequency, the number of waves, and time they take to pass?

Answer 11

f=N/t

Question 12

What is the formula for speed, frequency and wavelength?

Answer 12

v (units: m/s)
f (units: Hz (hertz))
lambda (units: m (metres))

Question 13

What is the range of human hearing?

Answer 13

20Hz - 20,000Hz

Question 14

What is sound below 20Hz called?

Answer 14

Infrasound

Question 15

What is sound above 20,000Hz called?

Answer 15

Ultrasound

Question 16

What does sound do when it meets a change in medium?

Answer 16

It reflects

Question 17

What is the speed of sound in water?

Answer 17

1500m/s

Question 18

What are the seven types of waves on the electromagnetic spectrum, from longest to shortest wavelength?

Answer 18

Radio waves, microwaves, infrared, visible light, ultraviolet (UV), X-rays and gamma rays

Question 19

What is diffraction?

Answer 19

The bending of waves around an object.

Question 20

Do longer or shorter wavelengths diffract more?

Answer 20

Longer wavelengths. Shorter wavelengths reflect more and bounce off of the change in medium.

Question 21

What is a use for radio waves?

Answer 21

Carrying radio and TV programmes. The long wavelength allows the waves to diffract around building and hills, thus reaching more receivers.

Question 22

What is a use for microwaves?

Answer 22

Cooking food and satellite communication

Question 23

What is a use for infrared waves?

Answer 23

Infrared waves is another word for heat. It can be used in thermograms and healing damaged tissue

Question 24

What is a use for visible light?

Answer 24

Lasers as scalpels, laser eye surgery

Question 25

What is a use for ultraviolet light?

Answer 25

Treating skin (acne), security markings on bank notes (can also cause cancer)

Question 26

What is a use for X-rays?

Answer 26

Creating images of bones inside the body

Question 27

What is a use for gamma rays?

Answer 27

Killing cancer cells, killing bacteria, tracers