Waves, Light and Sound test Term 2

Question 1

Describe how energy is transferred using waves.

Answer 1

Waves are the movement of energy from one place to another. Transferring energy without transferring matter.

Question 2

Definition of Transverse Waves

Answer 2

A transverse wave moves the particles up and down, at right angles to the direction the wave travels.

Question 3

Definition of Longitudinal Waves

Answer 3

A longitudinal wave moves particles back and forth in the same direction as the wave travels.

Question 4

Longitudinal areas

Answer 4

Compression and Rarefaction

Question 5

Compression

Answer 5

The part of a sound wave where particles are pushed close together.

Question 6

Rarefaction

Answer 6

Where particles are spread far apart in a wave.

Question 7

The difference between Longitudinal and Transverse waves

Answer 7

Longitudinal waves: Particles move back and forth in the same direction as the wave.
Transverse waves: Particles move up and down, at right angles to the wave’s direction.

Question 8

Amplitude

Answer 8

The height of a wave from the middle to the top. It shows how strong or loud the wave is.

Question 9

Wavelength

Answer 9

the distance between a point on one wave and the same point if the next wave. It is measured in metres

Question 10

Frequency

Answer 10

The number of complete waves that pass a point every second. It is measured in Hertz. 1 hertz equals 1 wave per second.

Question 11

Period

Answer 11

The time it takes for one complete wave to pass a given point. It is measured in seconds.

Question 12

Crest

Answer 12

The highest point of a wave

Question 13

Trough

Answer 13

The lowest part of a transverse wave

Question 14

Direction of Energy Transfer

Answer 14

The path or direction along which the wave energy moves

Question 15

Electromagnetic Spectrum

Answer 15

The entire range of electromagnetic waves.

Question 16

Radio Waves

Answer 16

Most commonly used from communication as they are large and can travel great distances. A radio wave is generated by a transmitter and the detected by a receiver.

Question 17

Microwave

Answer 17

Are generally between 1mm and 30 cm. Most common use is microwave ovens. The waves causes the water molecules in food to vibrate which is heat.

Question 18

Infrared

Answer 18

A type of light we can’t see, but we feel it as heat. It has longer wavelengths than visible light.

Question 19

Visible lights

Answer 19

Visible light is the part of the electromagnetic spectrum that we can see with our eyes. It includes all the colours of the rainbow, from red to violet, and travels in waves.

Question 20

Ultra Violet Light

Answer 20

Ultraviolet (UV) light has more energy than visible light but cannot be seen by the human eye. It comes from the sun and can help produce vitamin D, but too much can cause sunburn or damage skin and eyes.

Question 21

X-Rays

Answer 21

So small they can move through things easily. Used in medical field for viewing the inside of the body.

Question 22

Gamma Rays

Answer 22

The smallest wavelength caused by nuclear explosions. Are very dangerous to humans.

Question 23

Electromagnetic Spectrum order

Answer 23

Radio waves, Microwaves, Infrared, Visible light, Uv light, X rays and Gamma rays.

Question 24

Electromagnetic Spectrum difference

Answer 24

The different Electromagnetic waves are distinguished by their wavelength and frequency. (Radio waves to Gamma waves the wave length decreases and frequency increases)

Question 25

Light

Answer 25

A form of energy and a part of the Electromagnetic Spectrum. Light is a transverse wave. Light also travels in straight lines.

Question 26

Define Luminous

Answer 26

Luminous objects produce or emit their own light, such as the sun or lamps.

Question 27

Define Non-luminous

Answer 27

Non-luminous object do not produce their own light. They are seen when light from a luminous source reflects of them.

Question 28

Define Transparent

Answer 28

Transparent substances allow light to pass straight through without distortion. (e.g glass)

Question 29

Define Translucent

Answer 29

Translucent substances allow light to pass through but the light is distorted, interfering with clear vision. (e.g frosted glass)

Question 30

Opaque

Answer 30

Do not allow light to pass through

Question 31

Describe how objects are observed in a plane mirror

Answer 31

Light reflects off the mirror in straight lines. The reflected rays form a clear image that looks like it's behind the mirror.

Question 32

Regular Reflection (Specular reflection)

Answer 32

Happens on smooth surfaces. Light rays reflect evenly, creating a clear image.

Question 33

Diffuse reflection

Answer 33

Diffuse reflection happens when light hits a rough surface and scatters in many directions. This means we can see the object, but not a clear image like in a mirror.

Question 34

Incident Ray

Answer 34

An incident ray is the incoming light ray that strikes a surface before it reflects or bends.

Question 35

Normal

Answer 35

The normal is an imaginary line drawn at a right angle (90°) to a surface where the light ray hits. It's used to measure angles of incidence and reflection.

Question 36

Angle of Incidence

Answer 36

The angle between the Incident ray and Normal.

Question 37

Reflected ray

Answer 37

Is the ray that bounces of the surface after hitting it.

Question 38

Angle of reflection

Answer 38

The angles between the reflected ray and the normal. The angle of reflection and the angle of incidence are both equal.

Question 39

Refraction

Answer 39

Refraction is the bending of light as it passes from one material into another, changing its speed and direction.

Question 40

Density

Answer 40

Light travels slower in more dense areas. And speeds up in less dense areas. When light travels from a less dense areas to a more dense area it slows down ( bends towards the normal) and when light travels from a more dense area to a less dense area it speeds up (bends away from the normal). Higher refractive index = more dense

Question 41

Sound

Answer 41

A type of mechanical wave that moves through a medium. (Longitudinal wave)

Question 42

A mechanical wave

Answer 42

A mechanical wave is a wave that needs a medium (like air, water, or solids) to travel through. Sound waves are a common example of mechanical waves.

Question 43

How does sound travel

Answer 43

Sounds travels by the vibration of particles in a medium. When a sound source vibrates, it causes surrounding particles to vibrate transferr

Question 44

Pitch

Answer 44

Is how high or low a sound is perceived. It is determined by the frequency of the sound wave

Question 45

Sound frequency, wave length and pitch

Answer 45

Higher pitch = Higher frequency= Higher wavelength

Question 46

Relate Amplitude to loudness

Answer 46

The amplitude of a sound wave is related to it loudness. A greater amplitude results in a louder sound. Loudness is measured in decibels (dB).

Question 47

Sound travelling through mediums

Answer 47

Sound travels faster in more denser areas. Speed of sound is 343m/s in air and 1500 m/s in water.

Question 48

Echo

Answer 48

The reflection of a sound wave off a surface.

Question 49

Sonar

Answer 49

A system that uses sound echoes to detect objects underwater. A sound pulse is sent out and the stime for the echo to return is measured.