Statics: Lesson 65 - Challenging Friction Wedge Problem with Roller

[@manuboker1]

Wonderful Statics lessons!! really taking the time to explain the problems along with a good sense of humor :))

[@MinecraftWithRichy]

Is there a reason why we couldn't have avoided the moment equation by simplifying the 2 equilibrium summations of forces (x and y) by setting the friction F_B to a constant (mu_s=0.6) time the Normal at B? Solved via a system of equations for the N_B to use in the next free body diagram[the Wedge].

[@justinsantos5751]

It's probably because the state of the surfaces at point B was not stated or implied to be about to slip (under impending?) such that the value of the static friction is maximum Fs=(us)N. Remember that static friction is defined to be Fs≤(us)N. It is not always equal to (us)N.

[@michaelpuchalski6369]

Very helpful thanks Jeff

[@aleister8289]

Can't The big roller just move to left without rotating? I think this scenario is also possible.

[@BrysonOrison]

no because there is friction at B if there was no friction (perfectly smooth or lubed) then yes

[@brucelee1048]

i wonder how do we solve that problem if W is given already

[@janakassem838]

i dont understand the friction directions... i mean like u say if im the wedge id feel the wheel spinning clockwise an so thenfriction should be down ..but made it up

[@Natifrak]

Why when you made a diagram of forces did you not add the force of gravity multiplied by the mass in the bodies of the triangle and the sphere? (I'm talking about mg) at about minute 7:46.

[@olgunsaricam1419]

those already are forces. not mass (8 pounds)

[@ImranKhan-tu7ix]

I solved few starting problems and noticed in wedge problems Break Fs (friction force) into 2 components and break normal force which is acting on wedge or wedge applying,into two components

[@Sofialovesmath]

many thanks

[@leelee5269]

I stumbled upon your lessons while asking about the exposed tank rollers I see in Russian tanks used in Ukraine invasion. I wondered whether the mechanism used to remove a Caterpillar track was similar. I would like to link your site to a person who is a member of the Ukrainian Resistance. But am a dumb American heavy equipment operator who simply remembered this vulnerability of such heavily armoured vehicles during WWII.... I am pretty sure the combatants remember it tooooo. That typo represents the number of rollers on the tank photos i am seeing. I hope you are not offended by the pragmatic uses of engineering. Regrettably, Da Vinci, as well as others since the age of walled cities and sieges...have used engineering to siege and defend against sieges. I have known both WWII veterans from Russia, and Ukrainian immigrants to be very moral and ethical people. War savages civilians. That is it's primary purpose, I believe. Lebensraum, and Rape. Let's not fool ourselves. Nor neglect the tools of defense against hostile machines. Thank you for a very clear teaching style and for sharing this problem. I like your teaching style very much and have subscribed.

[@georgesadler7830]

DR. Hanson, thank for a powerful explanation and mathematical analysis of another Challenging Friction Wedge Problem with roller.

[@antesmauricejohn9067]

I thought when u do A moment you should include multiplying it with the distance. Why isn't it done here? Am I missing something?

[@10ursylmz]

Fa and Fb are acting on a circle tangentially, hence the distance is the radius. So the distance is equal.

[@russstobbe8263]

I don't understand what numbers he is putting into his system solver and where?

[@sebastiancurry3714]

hes using the TI 36x calculator which has a system solver that does all the algebra for him which can be done in either a 2x2 matrix or 3x3 matrix, in this one its 2x2, solving for 2 unknowns with 2 equations. Sounds a little confusing, but he has a video on his channel on everything you need to know about how to use the system solver, you can just look it up. So, I would recommend getting a TI 36x calculator and learning how to use the system solver from his channel if you want

[@notabot1078]

solving linear equation

[@solomonmule3414]

i dont know if am going to make it🥺😞😟

[@jefferyjoe5751]

did you?

[@solomonmule3414]

I did 💪🏼

[@jefferyjoe5751]

@@solomonmule3414 hard!..out here wildin waiting to make it in a week

[@parthimashru2045]

i love u

[@androsdrewry2878]

how the hell u get a moment equation at o

[@captainchicken7650]

malu u sik brapa paham

[@androsdrewry2878]

can u stop being too flamboyant when solving. stop openly assuming this and that is knocked out. WRITE IT TF DOWN. not everyone has braiinn like urs to see things non-physically to know its knocked out. its getting annoying

[@androsdrewry2878]

toward 13 minutes ur writing really isnt understandable. write properly