Science Physics Unit 1 Year12

Question 1

Define and give examples of a longitudinal wave

Answer 1

where particles vibrate parallel to the path of propagation e.g. sound

Question 2

Define and give examples of a transverse wave

Answer 2

where particles vibrates perpendicular to the path of propagation e.g. water ripples , guitar plucking , electromagnetic waves

Question 3

Define in phase and out phase

Answer 3

in phase is when points on a wave are plotted at the same position of the wave cycle , Out phase is when points on a wave are plotted at a different position of a wave cycle

Question 4

Define coherence

Answer 4

when two wave sources have identical frequency and waveforms and the phase difference is constant

Question 5

Define superstition

Answer 5

overlapping of waves e.g. large and small wave ripples

Question 6

Define stationary waves

Answer 6

two waves moving in opposite directions , having the same amplitude and frequency

Question 7

Define and explain diffraction grating

Answer 7

light is made up of several different colours , all of them travel in different paths at different frequencies

Question 8

Explain how to find wave speed

Answer 8

frequency x wavelength

Question 9

Define amplitude

Answer 9

the maximum extension of oscillation from the equilibrium

Question 10

Define oscillation

Answer 10

regular repetitive motion of going back and forth

Question 11

Define resonance and give an example

Answer 11

the storing of energy in oscillation/stationary wave, energy coming from a external source of frequency, strumming a guitar is an example

Question 12

Define a node in terms of standing/stationary waves

Answer 12

a point of zero vibration

Question 13

Define a antinode in terms of standing/stationary waves

Answer 13

the point of maximum vibration

Question 14

Define emission spectra/spectrum

Answer 14

range of frequencies of light emitted by a element

Question 15

State the equation for refractive index

Answer 15

n = c/v = sin(i)/sin(r)

Question 16

Explain the difference between analogue and digital signals

Answer 16

analogue uses a range of values to represent information, digital uses 0’s and 1’s binary

Question 17

What are the properties of different regions of the electromagnetic spectrum related to?

Answer 17

their frequencies and wavelength

Question 18

State the order of increasing frequency in the electromagnetic spectrum

Answer 18

radio waves, microwaves, infrared, visible light, UV, x-rays, gamma rays

Question 19

How much is a MHz?

Answer 19

10 x the power of 6 Hertz

Question 20

What waves are used for mobile phone networks?

Answer 20

radio waves because of their high frequency = greater bandwidth = large amounts of data being transferred

Question 21

What affects the signal for mobile phone networks?

Answer 21

wet weather, microwaves are strongly absorbed by it and terrain reduces the amount of diffraction in waves

Question 22

What waves are used for satellite communication

Answer 22

microwaves but radio waves are used for low orbit satellites

Question 23

Explain how satellites communicate?

Answer 23

microwaves pass through the ionosphere to satellites, radio waves are reflected by the ionosphere for terrestrial communication

Question 24

Define blue-tooth

Answer 24

wireless, short ranged radio waves that can connect electronics

Question 25

State the features of Bluetooth

Answer 25

connects multiple devices, range of 10m, uses short radio-waves so doesn’t need line of sight, uses frequency hopping to reduce interference

Question 26

State when infrared is used

Answer 26

low power devices like remotes

Question 27

State the features of infrared

Answer 27

short ranged = uses line of sight, high frequency signal = large data transmits

Question 28

What affects the signal for infrared waves

Answer 28

bright sunlight, atmospheric moistures reduces range

Question 29

What waves are for Wi-Fi?

Answer 29

radio waves between 2.4GHz-5GHz

Question 30

States the features for Wi-Fi

Answer 30

range of 100m, passes through walls, they can be transmitted through optic fibres/electrical wiring