Physics 6-others

Question 1

X-rays have what sort of frequency + wavelength?

Answer 1

high frequency

short wavelength

Question 2

For fluroscopes, what is used which decreases the intensity required from x-rays?

Answer 2

image intensifier

Question 3

how does ultrasound imaging work?

Answer 3

measures the it takes for an ultrasound to be reflected back from partial reflection

Question 4

What can ultrasounds be used for with kidneys?

Answer 4

used to breakdown kidney stones

Question 5

What can ultrasounds be used for with fetuses?

Answer 5

Ultrawaves reflect back from the fluid in womb + skin of the fetus and echoes reflected back are transmitted into an image

Question 6

What can ultrasounds be used for with blood?

Answer 6

Measure blood flow + see for any blockages

Question 7

what are the dangers of xrays and CT scans

Answer 7

They are both ionising

Question 8

What can be used to check % oxygen in the blood

Answer 8

Pulse Oximeters

Question 9

How do Pulse Oximeters work?

Answer 9

Patients with high oxyhaemoglobin levels will absorb the Infrared light meaning not a lot passes through

Anaemic patients have a low oxyhaemoglobin levels and dont absorb Infrared well

Question 10

WIth PET scans, what is inserted into patients?

Answer 10

Positron emitting radioisotope

Question 11

What happens when positrons and electrons colide?

how can this be used in medicine

Answer 11

they colide(annihalaiton) and create Gamma Waves

Tumour cells take up radio isotope more than normal cells

detection of gamma waves where radio tracer is found

Question 12

The resting potential in a muscle cell is what?

Whats the mV?

Answer 12

P.D across the cell membrane at rest

-70mV

Question 13

When SAN sends a pulse, what happens to the resting potential. whats this called?

Answer 13

Changes to +40mV

Action potential

Question 14

P wave defines what?
QRS wave defines what?
T wave defines what?

Answer 14

Atria Contracting

Ventricles Contracting

Relaxation of Ventricles

Question 15

Working out HR using ECG =

Answer 15

Frequency = 1/time period (peak-peak)

x60 = HR

Question 16

Why are there no green stars?

Answer 16

Stars are only red/yellow/orange/blue

Green will contain high red + blue = white

Question 17

Hot objects emit what?

What will they always emit more of?

Answer 17

radiation

Emit more of one frequency of radiation

Question 18

The peak frequency of a hot object depends on what?

Answer 18

temperature

the higher it is, the higher the peak

Question 19

Luminosity/brightness depends on what?

If a star is red what does this mean?

Answer 19

temperature

Cool star (low frequency)

Question 20

what is red in terms of frequency / temperature
what is orange
what is blue

Answer 20

low
medium
high

Question 21

Electrons with the lowest energy levels are found where?

Answer 21

near the nucleus

Question 22

Absorption spectra, why do gaps formed when continuous light is passed through a gas?

Answer 22

Electrons in the gas absorb certain frequencies of light

forms dark lines

Question 23

With emission spectra, why do bright lines form?

Answer 23

electrons fall from higher to lower levels and emit radiation of a particular frequency

Question 24

Each element has its own what (spectra)

Answer 24

own line spectrum

Question 25

What constantly releases a continuous spectrum of radiation from a star

Answer 25

Photosphere

Question 26

Using the photosphere what can this allow us to do with other stars

Answer 26

Work out the elements present

Question 27

with Doppler shift, the frequency of sound moving away from you, will do what with wavelength/frequency

Answer 27

moving away = lower frequency + longer wavelength

Question 28

With Doppler shift, the frequency of sound moving towards you, will do what with wavelength/frequency

Answer 28

moving toward= high frequency + short wavelength

Question 29

how does Doppler shift work with galaxies

Answer 29

light coming back to us, comes back at a increased wavelength = indicating red shift as its moving away from us

Question 30

red has what sort of wavelength?

Answer 30

large wavelength

Question 31

blue has what sort of wavelength?

Answer 31

short wavelength