week 12 DLISC tutorial Flashcards
(12 cards)
sound waves travelling through a wall is an example of what type of wave behaviour?
transmission
the human ear can normally hear pitches from sounds ranging from about…
20 to 20,000 hertz
a black surface becoming warmer when exposed to the sun is an example of what type of behavious of infarred waves?
absorption
the wavelength of a visible light is:
380 to 700 nanometers
complete the sentence
the lowest frequency of light we can see with our eyes appears…The highest visible frequencies, which are nearly twice the frequency of red light, appear…
the lowest frequency of light we can see with our eyes appears red. The highest visible frequencies, which are nearly twice the frequency of red light, appear violet.
which receptors in the eye are responsible for higher light levels or photopic vision?
cones
two examples of gravity forces on the body
the formation of varicose veins in the leges due to the venous blood travels against the froce of gravity on its way to the heart.
bone loses some bone mineral when a person becomes weightless such in an orbiting satellite, and this could be a serious probelm on very long space journeys
describe and give examples of frictional forces on the body
frictional force refers to the force generated by two surfaces that contact and slide against each other
friction in bone => synovial fluid in the bone joint helps in lubrication, however, some diseases such as arthiritus increases the friction in bone.
the heart, lungs and intestines are lubricated by a slippery mucus convering, to minimise friction
six properties of waves
amplitude
crest
trough
wavelength
period
frequency
four ways that waves interact with matter
absorption
reflection
refraction and diffraction
interference
what is the optic nerve
- carries electrical signals from the rods and cones to the brain
recieves light signals from about 125 million photoreceptors, which are the rods and cones
then the visual cortex converts the images impulses into the objects we see
