in this video we're going to have a look at how to use the phet simulation about color vision to investigate how white light is made up of different colors and the perception of our brain of what those different colors mean so we'll start off on this simulation with a single bulb down here and i've chosen a white bowl so turn on my torch here and you will see that when the white light shines at your eyes your brain perceives it as being white and you've got a couple of settings here so we can see the
light like that we can see it as little particles and you can see white light is actually a mixture of lots of different colors and you are probably aware of that because you will have seen what happens when white light is split apart with a prism so let's go back to that one if we add a color filter in front of the light so here is our filter option so maybe i could pick a blue filter and i pop the filter in front of the white light then all of the light is striking the filter
but only the blue light is being transmitted through and our brain therefore only receives that blue information we can change the color of our filter if you change to a green filter you'll see that now the dots are all hitting the filter but only the green is transmitting through and for a red filter only the red light is being transmitted through and our brain is perceiving different kinds of light let's take away that filter and our brain now perceives white light we can actually have bulbs of different color here as well so if i pick
a bulb which is green our brain perceives it as being green but we could add a filter and let's leave it as a red filter in front of it our brain now perceives no color coming through because the red filter is absorbing all the green and there's no red light being transmitted through because no red wavelengths of light are hitting the filter so you can have a play with different bulb colors and different filters another thing you can do is look at color perception by changing from a single bulb to three different bulbs so we
have a red light you can change the intensity of the red light here green and blue from different torches press play and when you do different mixes if we turn off the red and we leave the blue and the green then our brain perceives this color green sort of a dark green you could increase more blue and the color that our brain perceives changes so you can play with the different mixes of colors to see what different colors our brain perceives and if we turn all of them up to max our brain perceives that as
white light that mix of colors coming in at once so you can have a play with three different colors and see how our brain interprets the different color vision
