Scientific Notation and Dimensional Analysis

In science, sometimes we have to talk about very large and very small numbers. We need a special way to do this called scientific notation. We also need a way to convert between different units of measurement. I know, I know, you hate math. But it's really easy math, and Professor Dave will help make it even easier!

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[ProfessorDaveExplains]

Yikes! At 2:33 I accidentally put a nine at the end of all those zeros instead of a one, what a silly mistake! Also, there should be a zero before the decimal point. I was not as careful and thorough at the beginning of the channel as I am now, please forgive me!

[dbneptune]

I’m not watching this series for help in school, you just make it so fun that I want to learn this in my own time! Thanks Dave!

[maxidavis]

I just want you to know that I struggled with conversion/dimensional analysis throughout my Chemistry class and Engineering class in high school and this video was that moment where I got it. Thank you!

[elizabethlegaspi]

Thank you, Professor Dave for creating this page! I'm currently taking CHEM 10 online summer session and your video are extremely helpful. You cut the fluff and get straight to the point, which makes learning the "scary" chem material fun.

[ciarawalker]

Majoring in biochemistry. This fall will be my first semester. Better binge watch + take notes (even though I know most chemistry) the videos were too well done to just skip over!

[jermble]

Thanks so much!! I missed the class where we mentioned dimensional analysis and my teacher told me to watch this to get the general idea.

[Music-nnmi]

the absolute wonderfully helpful information made me disable my ad blocker

[philawsophy]

Currently studying this chemistry for my medical entrance exam. I am hoping I can finish the GenChem Series so I can proceed to OrgChem. Thank you Professor Dave.

[lightning]

I can do complex algebra and trigonometry, but for some reason I struggle with unit conversions. This video helped to fix that. Thank you so much.

[davidboygenius]

I love your videos! You're almost at a mil! Congratulations and keep making videos!

[Metskins]

Doubt you are still reading these but the conversion from km/hr to m/s only has originally 1 sig fig so shouldn't the resulting answer technically be 1 sig fig? I understand making sure we are doing the math right but I also want to make sure that using sig figs it would actually be 30 m/s

[supermanwithabeard]

I don't understand how you got 27.8m/sec with "Express 100km/hr in m/sec". I'm sorry, Professor Dave. I'm taking my first ever chemistry class (college) this year and I've never been good with math. This is throwing me off. I don't understand it and I'm getting pretty frustrated/discouraged. Where does the 27.8 come from? I know this is simple to you and others, but to me... I just don't understand how you arrived to that. I wish you would have worked it out in the video. I'm terribly confused. I appreciate your work, however, and I thank you for it all. Just really, reaaaally confused on that particular part.

[elizevdspuy]

Thank you Professor for sharing your knowledge and explaining in the needed an relevant information!! Your video's and small hits have helped me understand my work so much better. When my tutors don't know the answer I know you do!!

[MillionairesDiary]

i graduated highschool years ago but this is an awesome refresher. Feels good to comprehend

[stjonal]

Hello. Awesome channel, I am going to love watching what you make in the future.

One thing that bothered be though was your calculation of the number of seconds in a year at 4:07. You seem to have taken into account the significant digits. Under normal circumstances this would be correct, as the numbers with the lowest significant counts are the 60's and 24. However, these are integers with a defined unchangable size. They have no need for greater significance, since by definition there are only 60 seconds in a minute, 60 minutes in an hour and 24 hours in a day respectively. The only one that could be debated is the number of days in a year, since leapyears are a thing, and leapseconds accordingly. In a normal, non-leapyear there are exactly 31536000 seconds. no more, no less. For ease of use its good to give the scientific notation, but it distorts the number of significant digits in the number.

[jeanlanz]

Thank you for a wonderful video...One point, please...at 2:34.... 10^-9 is shown incorrectly. Thank you for generously sharing your knowledge. God bless.

[johnwilliamj.r]

Thank you so much Professor Dave, I never really payed attention in high school and somehow I made it to University to study Geology, now these series are being very very very helpful for me to catch up... thank you thank you...

[cptray-steam]

Wow I can do dimensional analysis now, previously I sucked at this stuff now I am somewhat decent at it thanks Dave. Now I just have to figure out how to memorize that table you showed that displayed the kilo = 10³ and stuff.

[syaoransakura]

Wow, this video tutorial is just really good. They even had tests in the end. Love it

[Abcdefghijklmnopqrstuvwxyz]

2:40 you can do that with any measurement unit you could use parsecs if you wanted