Y10 TERM 3 - Waves

Question 1

Amplitude

Answer 1

The amplitude is the distance between the line of the direction of travel and the furthest point that it vibrates away from the line

Question 2

Period of a wave

Answer 2

Time taken for the source to produce one complete wave

Question 3

Frequency

Answer 3

The number of waves per second, it is measured in hertz, Hz. You can think of it as how quickly the waves are travelling

Question 4

Wavelength

Answer 4

The distance between one point on a wave and the same point on the next wave; usually the point from the top/bottom of one wave to the (peak/through) to the top/bottom of the next

Question 5

Radio waves

Answer 5

• Uses: broadcasting and communications

- NO DANGER

Question 6

Microwaves

Answer 6

• Uses: cooking and satellite transmissions

- Danger: internal heating of body tissue

Question 7

Infrared

Answer 7

• Uses: heaters and night vision equipment

- Danger: skin burns

Question 8

Visible light

Answer 8

• Uses: optical fibers ( used for internet ) and photography

- Danger: blind / damage eyes

Question 9

Ultraviolet

Answer 9

• Uses: fluorescent lamps ( example: to tan your skin )

- Danger: damage to surface cells ( NOT BURNING SKIN ) and blindness.

Question 10

X - rays

Answer 10

• Uses: observing the internal structure of objects and materials, including medical applications.
• Danger: cancer, mutation

Question 11

Gamma rays

Answer 11

• Uses: sterilizing food ( killing bacteria ) and medical equipment
• Danger: cancer, mutation

Question 12

Reflection

Answer 12

Light hitting a reflective surface will ‘bounce’ back from the surface ( at the same angle they hit the surface )

Question 13

Refraction

Answer 13

Light waves change speed when they pass through objects of different densities, this causes them to change direction. When they return to the original density they will continue in the original direction.

Question 14

Angle of incidence

Answer 14

The angle of incidence is the angle that light hits a mirror; it is taken between 90 degrees from the mirror and the incidence wave ( the wave that hits the mirror )

Question 15

Angle of reflection

Answer 15

The angle of reflection is the angle that light leaves the mirror; it is taken between 90 degrees from the mirror and the angle of reflection

Question 16

Total internal reflection

Answer 16

• All of the light is reflected
• Inside a more dense medium ( material )
• Angle of incidence > Critical angle
• Light must be traveling from a more dense to a less dense medium ( material )

Question 17

Refractive index ( equation )

Answer 17

Refractive index = sin ( angle of incidence ) / sin (angle of refraction )

n = sin ( i ) / sin ( r )

Question 18

Wave speed ( equation )

Answer 18

wave speed = frequency x wavelength

v = f x h

Question 19

Frequency ( equation )

Answer 19

frequency = 1 / time period

f = 1 / T