Im trying to figure out how much torque/hp a 24" 250lb flywheel would have at 1800 rpm , and how much hp/torque would be needed to sustain that rpm once achieved. Any help ?
A rotating flywheel has rotational kinetic energy and a rotating object has a moment of inertia. The concept of torque in the context of a rotating object refers to the amount of torque required to accelerate the rotational motion. Once the object is rotating the amount of hp you need to keep it rotating depends on the friction of the rotating shaft or ball bearings.
Hi Prof. Biezen :) if we were given a coefficient of friction such that friction acts on both sides of the centre of the wheel where it is bolted to a rod, how would we incorporate the force of friction/work done against friction in our calculations?
Typically, work done by any force is Force x Distance (x cos (theta)) I would multiply the frictin force time the distance traveled per rotation ( 2 pi R)
could you help with vee belt used to transmit power from one shaft to another with small pulley the drive pulley going in a clockwise direction it rotates at 800rpm. the inuded angle of the vee belt is 45degrees and the coefficient of friction is 0.35. the slack side tensioner is 80N. neglecting centrifugal force and belt thickness what is the maximum power and torque that can be transmitted through the drive at the driven pulley.
@@MichelvanBiezen Absolutely you are right Sir. But while taking MOI of spoke, you have used R square instead of R cube... Except this you have explained excellent
+elgato volador For a point mass rotating about a fixed point, the moment of inertial is: I = m * R^2 For all other object where the mass is distributed, the moment of inertia is: I = k * m * R^2 where k is a number between 0 and 1. For solid disk, k = 1/2 For solid ball, k = 2/5 For hollow ball, k = 2/3 For a bar of length L rotating about its center, I = (1/12) m * L^2 For a bar of length L rotating about its end, I = (1/3) m * L^2
That's all well and good, but how do you know what k is beforehand? Is this just something that's been determined experimentally for varying shapes or is there a way that we can work it out? By the way I've been really enjoying your videos so far- teaching myself physics is now much less painful :D
dancinkayley, I know this is 9 months late but he has a playlist on just finding the Moment of Inertia of various solid objects. The moment of inertia is found by taking a definite integral and the shape of the object determines the k.
There is no kinetic energy in a moving mass there is force Mv squared kinetic energy is the energy of consistent work from a consistent force regards Graham Flowers
@@MichelvanBiezen I mean I want a book on mechanical physics containing these topics. Torque. Calculate the speeds in the gearbox. I hope you have understood my request🥰
Awesome, just what I wanted to learn. Thanks for showing the steps by steps calculation, you are a good teacher 💕👍
Thank you. Glad it was helpful! 🙂
Im trying to figure out how much torque/hp a 24" 250lb flywheel would have at 1800 rpm , and how much hp/torque would be needed to sustain that rpm once achieved. Any help ?
A rotating flywheel has rotational kinetic energy and a rotating object has a moment of inertia. The concept of torque in the context of a rotating object refers to the amount of torque required to accelerate the rotational motion. Once the object is rotating the amount of hp you need to keep it rotating depends on the friction of the rotating shaft or ball bearings.
Hi Michel! If we consider weight at end point of each spoke like Ferris Wheel, then what will be the moment of inertia I.
Then those become "point" objects with moment of inertia MR^2 and are added to the overal total
once again love your work!
S Joyce o.k.
Hi Prof. Biezen :) if we were given a coefficient of friction such that friction acts on both sides of the centre of the wheel where it is bolted to a rod, how would we incorporate the force of friction/work done against friction in our calculations?
Typically, work done by any force is Force x Distance (x cos (theta)) I would multiply the frictin force time the distance traveled per rotation ( 2 pi R)
@Michel van Biezen thanks :) your videos have been of invaluable help
forgot to say driven pulley is 400mm drive pulley is 150mm diameters
1:36 why MI of spoked wheel is 1/3 mr^2
Think of a spoke as a bar that rotates about its end. (since the length of the bar is equal to the radius of the wheel: (1/3) mL^2 = (1/3) mR^2
Hey Michel why didn't you use 4*ml^2/12 for the rods
+Akhil Kotha You will get the same answer either way. (Remember to double the mass to 2 kg for each rod and double the length as well)
+Michel van Biezen thankyou michel
could you help with vee belt used to transmit power from one shaft to another with small pulley the drive pulley going in a clockwise direction it rotates at 800rpm. the inuded angle of the vee belt is 45degrees and the coefficient of friction is 0.35. the slack side tensioner is 80N. neglecting centrifugal force and belt thickness what is the maximum power and torque that can be transmitted through the drive at the driven pulley.
Some calculation mistake while taking moment of inertia of spoke instead of R cube you have taken R square. And answer should be 76.64 J
The video is correct.
@@MichelvanBiezen Absolutely you are right Sir. But while taking MOI of spoke, you have used R square instead of R cube... Except this you have explained excellent
is there an easy way to memorize the equations for the moment of inertia of the most common bodies?
+elgato volador
For a point mass rotating about a fixed point, the moment of inertial is: I = m * R^2
For all other object where the mass is distributed, the moment of inertia is: I = k * m * R^2 where k is a number between 0 and 1.
For solid disk, k = 1/2
For solid ball, k = 2/5
For hollow ball, k = 2/3
For a bar of length L rotating about its center, I = (1/12) m * L^2
For a bar of length L rotating about its end, I = (1/3) m * L^2
That's all well and good, but how do you know what k is beforehand? Is this just something that's been determined experimentally for varying shapes or is there a way that we can work it out?
By the way I've been really enjoying your videos so far- teaching myself physics is now much less painful :D
dancinkayley, I know this is 9 months late but he has a playlist on just finding the Moment of Inertia of various solid objects. The moment of inertia is found by taking a definite integral and the shape of the object determines the k.
There is no kinetic energy in a moving mass there is force Mv squared kinetic energy is the energy of consistent work from a consistent force regards Graham Flowers
KE = (1/2) mv^2
@@MichelvanBiezen what is in the other half
there is no other half. That equation represents the total kinetic energy of any moving object.
@@MichelvanBiezen what ever you say
So there are not two halves in a mass of an object
on the board it should be KErotational not KEtranslational right?
yes
at 0:53
thank u soo much how we can calcule the capacity??
Sorry. Not sure what you mean by "capacity". Are you referring to a different video?
@@MichelvanBiezen I think they're talking about heat capacity
Why 8 is multiplied with moi of spoke??
there are 8 spokes
Hi! Just a quick question. Why is the inertia multiplied by 1/3 at 1:45? Is it a formula?
The moment of inertia of a long pole rotating about its end is: I = (1/3) ML^2
Michel van Biezen okay, thankyou!!
where can i get the book! !!!
These videos are not specific to a single book.
@@MichelvanBiezen I know. but i am asking about a book includes all these objects 🥺
Every major text used at the university level will have these types of problems in it. The best is to pick the one you prefer. (They are all good)
@@MichelvanBiezen I mean I want a book on mechanical physics containing these topics. Torque. Calculate the speeds in the gearbox. I hope you have understood my request🥰
If you used 4I^2 for the rods and then use 1/12mL^2 for the ineria , you'd get the same answer?
+Jimi Hendrix Try it and see what happens. Best way to learn.