P6- Other Applications Of Physics

Question 1

CT scans

Answer 1

Use x Ray’s to produce high resolution images of soft and hard tissue

Question 2

Fluoroscopes

Answer 2

Patient between an X-ray spice and a flourescent screen
Xrays reaching screen will vary
Image intensifier means a lower dose of xrays given

Question 3

Use of ultrasound in medicine

Answer 3

Breaking down kidney stones
Prenatal scanning of fetus
Measuring speed of blood flow

Question 4

Endoscope

Answer 4

A thin tube containing optical fibres that let surgeons examine inside the body
Two bundles
One light and one imagine back
Keyhole surgery

Question 5

Pulse oximeters

Answer 5

Use light to check the %oxygen in the blood
Emits two beams of red light and has a photo detector
Amount of light absorption depends on the colour of the blood (red = oxyhemoglobin)

Question 6

PET scanning

Answer 6

Positron/ electron annihilation
Positron emitting radioscope is injected into a patient
Collide with electrons in organs and annihilate and emit gamma
Higher in tumour cells
Detectors detect each pair of gamma rays

Question 7

Resting potential of a muscle cell

Answer 7

-70mV

Changes to +40 mV when stimulated
Action potential

Question 8

What do ecgs measure

Answer 8

Action potentials of the heart