00:01
Okay, this question is asking us to estimate the wavelength of a particle moving very fast.
00:07
So, using a altered version of debrogly's equation, we can say that wavelength is equal to plank's constant divided by square root two times the mass of the particle times the kinetic energy of the particle.
00:29
Okay? and we can find the kinetic energy, which is equal to one half mass of the particle times velocity squared.
00:41
We know that the velocity is in the mass, so we can find the kinetic energy, which is one half, 1 .673 times 10 to the negative 27 kilograms.
01:10
Applied by the speed, which is 2 .9 times 10 to the 8 meters per second.
01:19
And that is going to be squared.
01:29
Just that.
01:30
So kinetic energy comes out to be, once we plug it into the calculator, negative energy is 7 .03 times 10 to the negative 11th joules.
01:44
And since we got joules as our variable we know that that's at least we know we got the we got the units correct because jules is a units of energy and when we go ahead and cancel out when we go ahead and do this kilogram times meters per second times meter squared over second squared is also known as jules so when we go ahead and plug the kinetic energy mass and planks constant into the equation we get that plank's constant is 6 .63 times 10 to the negative 34th joules per second we're going to go ahead and set the square root of two times the mass of the particle which is 1 .673 times 10 to the negative 27th kilograms times the kinetic energy this is still under the square root which is 7 .03 times 10 to the negative 11th joules so when we plug all of that into the calculator we get that the wavelength for this particle which is traveling almost as fast as the speed of light is going to be 1 .36 times 10 to the negative 15 meters now this question asked for the wavelength in nanometers...