Rotation and Torque - Physics 101 / AP Physics 1 Review with Dianna Cowern 

Hello, if ur reading this, I just wanted to tell you something. It's unlikely you probably are, cos coment sections fill up so first and I am sorry if there are any typos. I am blind, and my ambission is to become a scientist, it's been that for as long as I can remember. I am so glad I found your channel, your vids inspire me so much!

"Spin isn't a very physicsy word." Particle physicist: "Hold my boson."

16:52: "Another great way to get a handle on how torque works..." I see what you did there!

Love these series. They helped me grasp even more from my physics class and be able to have a better approach to solve problems. Thanks.

I was yelling Centre of Mass when she tossed the letters in the beginning 😁

I'm actually still in middle school,and my dream is to become an astronomer,thank you for making physics not look so intimidating. Love from Montenegro❤

Math-aficionados: Yeah that makes sense. Everyone else: **confused math noises**

Love how passionate Dianna is on science. I love science, but don't often see others have such a joy and enthusiasm for it like Diana does! Keep it up.

That looks like a 33 1/3 RPM record to me. At 45 RPM you get chipmunks singing.

Thank you Dianna for all your physics videos they help us to understand how much physics is important to us even in our daily life. Lots of Love from India🇮🇳🇮🇳🇮🇳🇮🇳❤️❤️

Another simple way to explain torque in basic terms. Door handles are placed towards the ends of doors (away from the hinges). The reason is because Torque increases with increasing distance from the centre. And hence doors are easier to open when the handles are placed towards the edges and not near the hinges

You put a lot into this Professor, I will have to watch it a couple more times to soak it all in. Great Job!!!!

_Just remember that you're standing on a planet that's evolving_ _And revolving at nine hundred miles an hour_ _That's orbiting at nineteen miles a second, so it's reckoned_ _A sun that is the source of all our power_

Really grateful that Diana's RU-vid video always gives me beliefs while I face hard times in my Physics Modern Optics course.

Great video Diana. You elucidate difficult ideas very well. You’re the best!

Thank you, Dianna! I've learned a lot from your videos! Kisses and hugs from Romania! I wish you a Merry Christmas!

This is excellent Dianna. I am very much proud of you! Keep Up the Good Work.

This will definitely help for my term exam tomorrow... Thanks Dianna !!🤓

This is something that I wanted to understand for a looonnnnggggg time.,... thank you soooo much Dianna

Such a wonderful enthusiasm you have for physics! Thank you very much!

Great video! I’ll have my students watch it. Never thought about the rotation of the earth reducing our weight... and will definitely use it as an activity. Thanks!

Every time I watch a video from Physics Girl, the excitement and enthusiasm for physics from her puts a smile on my face!

Door knobs on the show "Family Affair" were also in the center of the door.

I got genuinely excited at the screwdriver revelation when you compared the radii of the handle and the screw... This is why there is beauty in everything, you just have to look for it!

Love your Videos! 💕 I'm taking an 11th grade Physics course, and this is really an amazing supplement to my studies : )

I love you!!! I can't not stop watching your shows non stop.

I am an Aerospace Engineer at UB and I still watch your videos... they are amazing how you explain everything

Haven't watched yet , but something have wanted to learn for Soo long

Thank you Miss Diana !!! U make a lot things understand much clearly than a lot others

Thank you so much for creating and sharing this educational and entertaining video. Great Job. Hope that each day you are feeling better than the day before

Eventhough I already understood this lesson in my classes I keep watching for you physics girly. And it worths a lot and gives me very different perspective. I am so proud to be your student💕💕

I wish you and your a happy New year and look forward to many more enjoyable videos.

Honestly, I don’t need to (re-)learn any of this, I’m very past high school, and I actually remember most of the theory (even if the formulæ escapes me). But I love listening to Dianna, she could narrate a river flow for 5 hours straight and I’d be there with my eyes closed. One of the sweetest people on this platform.

Thanks for putting efforts in making these videos Really enjoyable.

I don't know any advanced math, but do know from riding my 650 Triumph Tiger motorcycle, that engine torque is what powers me up a steep hill....or, around another rider in a curve.The Triumph has tons of torque. Centripetal mass in a running motorcycle engine is also very complicated to my brain. Love all your posts Dianna. You're the "living end" as we Beatniks used to say of something that was way neat and superior.

I just finished physics and am only just now getting recommended these..... I really could have used these 4months ago lol damn it! Great videos they are really clear and fun to watch!

Changed my thought of rotation concepts good job Diana Ma'am

I'm in university right now and I've already done these parts of physics ages ago but it's still great refreshment and wonderful entertainment.

Hobbit hole doors would have the door knob on the side if the author was J.R.R. Torquien.

This is a great video. Just like records, we can adapt the lesson to vehicles and machinery. For example, the use of torque as a standard unit of measurement to help communicate the performance of diesel/gasoline engines and electric motors. Then later how they transmit the rotational torque to the tire then use it with friction to transfer to linear motion of the vehicle.

Great video. Thank you. I would love to hear more about angular acceleration.

19:54 who else thought she was gonna fling that hammer in the air? haha

Thanks for all your videos

As I was studying Computer science we had a subject Physics our lecturer asked a question "Imagine we have a disk that is spinning, in a random moment a chunk of this disk is detached. What happens to the to disk?" Nobody else knew the answer. So, I raised my hand to talk. "Due to the fact that the mass of the disk initially is universally distributed across its body. When a chunk of disk is detached then the mass is not any longer equally distributed so the dusk has a new center of gravity and it changes how it is being rotated." All other students were amazed by this answer.

This is so fun to watch!

thank you, Diana. I really needed help with torque

Thank you Dianna 😀 Becuz yesterday in my test they asked what is the angular velocity of earth 🌎 And I saw the video the day before so it helped me a lot.

When this series ends are you going to start filming a more advanced course?

Humor is how I remember things. Torque is represented by the symbol Tau, therefore I remember they are related from the word Twerk. Every time I think of this I laugh to myself.

I searched for rotational kinetic energy and Your video helped me very much 👏Thank you🤝

All mother of pure and good I have exam on this tomorrow And u are here to help me

Torque, it's handy to note, is the detailed explanation of the mechanical advantage of a lever, which is why it amplifies the effect of the force by applying it through a longer distance.

Wishing our dear Physics Girl and to all of us physics lovers a very merry Christmas 🎄

To be precise, you should use the sidereal day (86164 s) when calculating the earth's rotation. The contraction along the circle of rotation is significant in a neutron star. I have a hard time picturing the geometry of a neutron star.

I love you Dianna ❤️ you are the best educator ever!!!! I didn't expect that there could be so much physics hidden in a screwdriver. 🤯

@Physics Girl You are using 86400s as one turn of the Earth, but it is not that. Keep in mind that the Earth goes around the sun and so a turn with respect with the sun is different than with respect distant stars and galaxies. Effectively, the Earth turns one extra turn per year in about a year (and about 20 minutes extra in that year). In other words, a sidereal day is about 23Hours 56 minutes or about 1 degree per day less. This may seem small, but it does add up over a year to the point that an extra sidereal day pass per year. Try 86164 s.

Loving these 101 sessions... keep it coming

I have thought of it what I was in my teens, I fell in love with physics and science then!!

Thank you, Lovely Lady! That lecture brings concepts to mind that under normal circumstances never get noticed! The balance between the rotational velocity and gravity keeps us from flying off into space, but doesn't crush us. Likewise on the moon, although we can jump much higher, So if we find a planet the same size and mass as the Earth, but it spins 20 times as fast, it may not support life as it is on Earth.,

There's another significant reason why door-handles are on the edge rather than in the middle - because that's where the door latch is - a door handle in the middle of a door that's a meter wide would need half a meter of mechanism to connect it to the latch; one on the edge needs maybe a centimeter. The stereotypical bank vault door engages with the frame all around, rather than just on the edge away from the hinges, so the handle there is centered (though there may also be a hand-hold at the edge for better torque). I'd also like to share a life hack for screwdrivers - if youre faced with a particularly stubborn screw, you can use a pair of pliers (or a monkey wrench) to grip the screwdriver and provide a long lever arm to use to boost your torque. Use with caution though since a thoroughly stuck screw can require an amount of force very close to the amount required to break the screw-head.

Thanks for another video for learning physics :)

3 points to note, 1: Diana is extremely excited that she managed to catch the pen, 60kg is a tiny human, and Diana says she is running out of room during the conversion of earths lineal velocity to rads yet the paper goes on for the rest of the video. Also from looking at the comment section, I don't think people understand the boring side of physics, being the very basic beginners to the yr11 students, you will be using this for your entire physics carrier, you don't get to move up, you just add more equations, but you will always be using the fundamental ones as well, for ever, none of them go away

This speaks to me on so many levels , not least VINYL!

I remember getting into an argument with some classmates in high school. I was in the machine shop class where most kids were burnouts. They told me if you fall from a high place and are standing on something. Just as your about to hit the ground you jump and nothing happens. I told them to just keep smoking pot because there is no future in there life. Momentum

The main reason doorknobs are on the edge is the mechanism need to latch and open the door (and deadbolt). A knob in the middle would need a large drawbar out to the edge of the circumference and would get flimsy. The hobbit door can still be pushed at the edge, for instance right hand on the know, left hand pushing in.

Tangentially (lol), I find the circumference of the earth easier to remember than the radius, because the meter was originally defined as one 10,000,000th of the distance from the equator to the North Pole (via Paris, maybe?). Anyway, that's travelling 90 degrees around the earth; a full revolution/circumference is therefore about 40,000 km.

This is your good turn for the day Diana ;-)

You have a really nice writing style ..:)

The length of the screwdriver has an effect also. It's easier to torque a screw with a longer screwdriver. The screwdriver can be at a small angle and you get a bit more torque.

Thanx mam bcoz of you my concept are becoming very very strong.

Class 11th, needed this!

amazing video !!!!

Even without talking about length contraction, rigid objects cannot exist in relativity because impulses from the point of application of the force to the rest of the body cannot reach the speed of light, so if a rotating body has a tangential velocity close to speed of light, or if it is very long, then the impulse has not yet reached one part of the body that the point of application is already very far away, resulting in an evident distortion of the body for any type of material.

Thanks a lot

The door knob example might not be the best eg to use as both scenarios are still workable. I suggest that knobs closer to the side are possibly due to easier installation & less complicated latching mechanisms required ?

I am at the yeah will take your word for it ! WAYYYYYY beyond me

I am a high school student and I am very confused in thermodynamics, My confusion is that :In physics, when we study thermodynamics, we say that we cannot find the work done in irreversible processes because in such processes the different state variables of the gas are not defined. For example, the pressure in different regions of the system is different when a gas expands quickly. Yes, I also agree with that. We cannot directly find the work done in such a process, because we don't know what pressure of gas should we take, but I think, even if we cannot calculate this directly, we can calculate this indirectly like we do in chemistry. In chemistry for example, when we find the work done in irreversible compression, we can find how much work is done by the surroundings on the system because the pressure of the surroundings almost remains the same. Let's assume +W amount of work is done on the gas, so it means that it has increased the internal energy of the system by +W (assuming no heat is released), so it also means that surely the work done by the system on the surroundings will be −W; to absorb that much energy, it has to do −W amount of work on the surroundings, and there is no other thing from which energy can be exchanged. So, all I want to ask is: Why we don't do it like this in physics? What's wrong with it? Why do we say that we cannot calculate work done in irreversible processes like this? Please guide me towards the right path without using higher mathematics just explain it in brief, then it would be easier for me to understand.

lovely diaana love your classes

Who would love to see an electromagnetism course,? I say because of the formula she has in the back hanged, it would be so cool to see her teach such an amazing topic!

From exploration to teaching👍👍👍

Good video (as always) You're still missing that gyroscopes can be spun (while spinning) and create linear thrust. *I've done it. It works Think of a gyro in place of a propeller on a plane, and the plane is a ride on a merry go round. If the gyros are spinning very fast AND the merry go round is spinning very fast you would actually get the merry go round to fly up. (You would actually need a duplicate set up counterrotating just like a set of blades on a helicopter would) I call the effect "Positive gravity"

I love you. You are making my life so easy🙂

Crazy ! I'm subscribed to you but I never ever ever get a notification for your videos..?

Love it ❤️❤️

You're a life saver btw

Enjoyed your video presentation. What if you use a Right Angle (90 degree) screwdriver to increase the radius, thereby increasing the torque (since according to your formula both the force and the radius are directly proportional to torque).

If an object is red then it absorbs all other wavelengths except red. Then what happens to absorbed energy. After absorption the object must emit the same energy after sometime right. So after sometime along with red all other wavelengths should also emit so every object should be white. Why this is not the case. Explain in terms of orbits of electrons around nucleus.

Learning is awesome.

This was a tough lesson. Had to stop a few times and let it sink in. Would be great to have you do a torque lesson as it applies either to automobiles or even one to sports like swinging a golf club or throwing a ball.

So when you work on an engine and add what my Dad called a breaker bar (a pipe slid over the end of the wrench to lengthen it.) You a adding a torque multiplier?

what is the background music at the beginning of the video?

Thanku sooooo much for your awesome lessons. Lots of love from India😊😊

Thanks it's helpful for jee

The EM drive can't give thrust but can it ad torque

Every fact in science must first undergo seven stages of evolution 1st is the idea 2nd is the concept 3rd is a cursory hypothesis AKA plausibility 4th is a working hypothesis 5th is a plausible theory 6th is a working theory 7th is accepted fact within the limitations of current math and science . Now I know your question what is a cursory hypothesis it is when your hypothesis is still too weak to test whether or not you can disprove it it is when your hypothesis is so new that you must first prove if it is even plausible if you can prove it plausible then it is elevated to trying to disprove it

Torque concept is indeed much interesting than I thought.

Hey , Dianna at 3:21 , Isn't our earth in Spherical Shape , So The Distance is its Total Surface Area , Right ?

Circumference of Earth: 25,00 miles Hours in a day: 24 A bit over 1,000 mph

Hi Dianna! Your videos have inspired me and I want to now major and study physics and want to become a physicist soon. Do you have any tips for people who want to study physics?

Happy Holidays!