A chemist in an imaginary universe, where electrons have a different charge than they do in our universe, performs the Millikan oil drop experiment to measure the electron's charge. The charges of several drops are recorded here. What is the charge of the electron in this imaginary universe? Drop # Charge A -6.9 * 10 - 19 C B -9.2 * 10 - 19 C C -11.5 * 10 - 19 C D -4.6 * 10 - 19 C

Video transcript

Welcome back everyone to another video, a chemist in an imaginary universe where electrons have a different charge than they do in our universe performs the Mican oil chop experiment to measure the electrons charge. The charges of several drops are recorded here. What is the charge of the electron in this imaginary universe? And we're given four different drops, their corresponding charges and four answer choices. What we want to do is first we identify the smallest charge which belongs to drop D and find the ratios of each charge relative to drop D. The reason why we're doing this is because we have a multiple of an electron charge on each chop and finding those ratios will essentially help us determine the charge of an electron. So essentially what we're going to do, we're going to start with a and to find the ratio, we can notice that all of the charges have the same sign, the same exponent. We have identified the lowest 16.2. So we're taking 9.3 and dividing that value by 6.2 which is the lowest one. If we find this ratio, we end up with 1.5. Now let's find the ratio for B we're taking 12.4 dividing by 6.2. This gives us 2.0. What about C? Well essential? We have 15.5 and we're dividing that by 6.2 which gives us 2.5. Eventually, we can immediately say that D is 6.2 divided by 6.2. This gives us 1.0. What we notice here is that some of these numbers are not whole numbers. So to make them all natural numbers, we are just going to multiply each of them by two. So essentially 1.5 becomes 3.0 2.0 becomes 4.0. Now for C 2.5 becomes 5.0 and 1.0 becomes 2.0. We want to make sure that we get the whole numbers. We did that multiplying all of our previous results by 22.5 were A and C. And now from here, what we want to do is essentially divide each charge by the resultant factor. So now charge A, let's call it C A would be negative and 9.3 multiplied by 10 to the power of negative nine. And we're dividing that by 3.0 which gives us negative 3.1 multiplied by its sense of the power of negative 19. And we can carry on to make sure that we get exactly the same charges for the remaining jobs charge relative to B would be negative 12.4 multiplied by 10 to the power of negative nine scenes divided by 4.0 which gives us the same value. So we are good charge C we take negative 15.5 multiplied by 10, the power of negative 19th. And we divide that by 5.0 we get the same result. Finally charge from D. We take negative 6.2 multiplied by 10 to the power of negative 19th. And we divide by 2.0 we still get the same number. Meaning we have verified that this would be the charge of the electron in the imaginary universe. Of course, all of these numbers are given in Coombs and we can state that the correct answer to this problem is option, a negative 3.1 multiplied by 10 to the power of negative 19th. Thank you for watching.