Banked Curve with Friction: Finding Maximum and Minimum Speed

Поділитися
Вставка
  • Опубліковано 28 лис 2024

КОМЕНТАРІ • 85

  • @AndyZengtheGreat
    @AndyZengtheGreat 5 років тому +57

    This is by far the best video for banked curves because it covers the general case.. Thanks a bunch!

  • @pastarizzoto
    @pastarizzoto 6 місяців тому +2

    This vid is the GOAT for this concept. Keep coming back to it multiple times

  • @nivlanait
    @nivlanait 4 роки тому +15

    This video is actually terrific!
    The concepts helped me adapt the FBD for upside down banked curves as well!
    10/10, shared it with the Physics C bois
    Keep up the great work man!

  • @seanmok9026
    @seanmok9026 3 роки тому +7

    Finally, I understand how he friction acting down/up the slope at the min./max speed. Thanks 👍

  • @jmmifsud1
    @jmmifsud1 4 роки тому +25

    Fantastic - so clear and simple - makes a lot of university lecturers look like twits

  • @pipertripp
    @pipertripp 5 років тому +7

    nicely done. Thx for doing the general cases. Was a good check for my problem set.

  • @RepelGG
    @RepelGG Місяць тому +1

    This helped a lot, thank you.

  • @tho_norlha
    @tho_norlha 4 роки тому +3

    It’s 11:12 pm right now, I’ll watch your video tomorrow and thank you for what you do

  • @jamieporter9356
    @jamieporter9356 4 роки тому +3

    thank you for the video! Much better explanation than my physics c teacher...

  • @angelinebantillo3128
    @angelinebantillo3128 4 роки тому +3

    You deserve more likes and subscribers.

    • @PhysicsNinja
      @PhysicsNinja  4 роки тому +1

      Tell your friends!!! Thanks for watching, I appreciate your support.

  • @aidantorres1094
    @aidantorres1094 Рік тому +1

    video helped a lot for my physics midterm! voice sounds like lightning mcqueen is teaching me racing physics

  • @galtbarber2640
    @galtbarber2640 Рік тому

    Thanks for the Excellent video! It was helpful showed the simple way to convert between the sin and cos version to tan by just dividing them all through by cos. That makes it much easier to compare to results from other sources.

  • @mapleint997
    @mapleint997 Рік тому +2

    This exact question showed up on an MIT 8.01 pset. Thanks lol

  • @apip258
    @apip258 3 роки тому +1

    You deserved more likes, thank you😉

  • @azrielshacham6829
    @azrielshacham6829 3 роки тому +2

    Great explanation

  • @lisandrolisandro8100
    @lisandrolisandro8100 Рік тому +1

    Thank you. Made a lot of sense

  • @FarhadADeven
    @FarhadADeven 5 років тому +6

    thanks a hell of alot

  • @camileclere8925
    @camileclere8925 2 роки тому +1

    i really struggle with knowing where to place theta. Could you briefly explain, or provide a link to a video that does? rest of the video is great!

  • @HociniMalak
    @HociniMalak 2 місяці тому

    Thank you , but I was wondering about the minimum speed because I couldn’t calculate it since the expression under the square root was negative.

  • @katievillasenor2268
    @katievillasenor2268 4 роки тому +2

    AMAZING thank u ninja

  • @03.lamyenchan12
    @03.lamyenchan12 Місяць тому

    how can you know which direction the friction vector is pointing if the problem doesn't give u the information that it is a fast or slow case?

  • @mashanatanzon557
    @mashanatanzon557 7 місяців тому

    Great video! Why can we not initally say that N =mg. This way we would only have to consider one dimension. For example for x it ould be mgsin(x)-umgcos(x)=mv^2/r. Then all m's could cancel. However it gives rise to a different answer then the one you found later for v. Why is this? Thanks :)

  • @utsavsharma4542
    @utsavsharma4542 4 роки тому +1

    Great explanation sir.

  • @petergoh5628
    @petergoh5628 3 роки тому +2

    Why is friction acting in the opposite direction for the second case?

    • @PhysicsNinja
      @PhysicsNinja  3 роки тому

      Friction will act to oppose motion. Consider the case where the car isn’t moving. Here friction tries to hold the object on the slope and acting up the ramp.

  • @prime3333
    @prime3333 5 років тому +2

    Why is the static force acting down the ramp when it's max speed, why is it acting up the ramp when it's minimum speed.

    • @PhysicsNinja
      @PhysicsNinja  5 років тому +2

      Take the case when the speed is 0, in that case the force of friction would be up the ramp because the car would want to slide down the ramp. same is true for small value of speed.

  • @ilnec
    @ilnec 2 роки тому +1

    You are a godsend

  • @CAshishRaj
    @CAshishRaj 4 роки тому +1

    Thanx sir , all doubts clear.

  • @nicholas_harry
    @nicholas_harry 2 роки тому

    If we add the center of gravity and the distance between the tires to this same situation, would it affect the problem in anyway? Because Im stuck on a question where they also gave the center of gravity height and the distance between the tires

  • @domigo_8678
    @domigo_8678 3 роки тому +1

    At what speed does the friction switch direction?

  • @MichelleHugli
    @MichelleHugli 2 роки тому +1

    Thank you 🙏🏼

  • @manuelrivera7446
    @manuelrivera7446 Рік тому

    What would the proper alignment be of the vehicle on a 33 degree Banking.

  • @pierusa123
    @pierusa123 2 роки тому +1

    when you measure the radius. do you measure it horizontally. or measure it along the banked road?

    • @PhysicsNinja
      @PhysicsNinja  2 роки тому

      Horizontal

    • @pierusa123
      @pierusa123 2 роки тому

      @@PhysicsNinjaThanks. The reason that I ask is because in your video Banked Curve Physics - Uniform Circular Motion, at time 13.24, the line R = 1100 ft looks like it is from the center to where the car is along the ramp, rather than from the center to the horizontal projection of the car. Other than that, you explanation is really good.

  • @karadjovalisa5924
    @karadjovalisa5924 3 роки тому

    you helped me out so so so much !!! thank you amazing video

    • @PhysicsNinja
      @PhysicsNinja  3 роки тому +1

      It’s comments like yours that motivate me to make more videos.

  • @venkataramanahegde1087
    @venkataramanahegde1087 Рік тому +1

    How friction is towards the radius,not along road

  • @elliekongnamul
    @elliekongnamul Рік тому +1

    Thanks a lot for this video! Was really helpful. I recently started to learn physics and am not sure why we should use static friction than kinetic friction here :-( Could anyone explain it a little bit? Thanks a lot in advance!

  • @petergoh5628
    @petergoh5628 2 роки тому

    Hi, I have a homework question that ask “why is the max speed for banked roads generally lower than roads that are flat?” But isn’t the max speed for banked roads higher? I tried substituting in values of theta and mu and the banked road gave a higher max speed

    • @PhysicsNinja
      @PhysicsNinja  Рік тому

      The bank is usually not uniform especially near the point where you leave the bank. If it’s slippery and the and the angle is small this would really be unsafe. Better to play it safe and reduce the speed limit.

  • @sealz4948
    @sealz4948 Місяць тому

    Thank you good sir

  • @ef6093
    @ef6093 4 роки тому +1

    Sir, may I know why we do not resolve the force as what we will do in the case of a block sliding down the slope?

    • @PhysicsNinja
      @PhysicsNinja  4 роки тому

      For a block sliding down a slope the acceleration is down the slope so we break down the forces into components using a coordinate system that has one axis along the slope. For this problem the acceleration is toward the center of the circle. It's easiest to use a coordinate system with one axis toward the center of the circle and break forces down into those components.

    • @ef6093
      @ef6093 4 роки тому

      @@PhysicsNinja oh. Ok. Thank you. May i know how is the dynamics of a cyclist bending the bicycle during a turn?

  • @vijgenboom2843
    @vijgenboom2843 2 роки тому +1

    Again, great! ❤️

  • @blakelazeski5974
    @blakelazeski5974 4 роки тому +1

    The picture is actually of Daytona lol. Nice informative video though.

  • @rbm4866
    @rbm4866 4 роки тому

    Thanks sir...It was really helpful

  • @ritesha8050
    @ritesha8050 2 роки тому +1

    thanks

  • @aasmaghosh5363
    @aasmaghosh5363 4 роки тому +1

    Very helpful...

  • @robertosabinospina1066
    @robertosabinospina1066 4 роки тому

    The Fast Case is odd. If you happen to have mu = 1 and an angle > 45 degrees, you get a negative square root (which does not exist). Does that mean that the body will never slide (i.e. You can go as fast as possible)?
    EDIT: Actually, there is a HUGE mistake in the fast case, before using the 1st equation to get the Vmax, you isolated the N in the 2nd equation, but YOU CAN'T do that if the angle = 45 and mu = 1, because you would be dividing by zero. Something is very wrong with this model

    • @PhysicsNinja
      @PhysicsNinja  4 роки тому +1

      No mistake, trust me. This is a great question and I’ve answered it before. See below comment from Lavender

    • @robertosabinospina1066
      @robertosabinospina1066 4 роки тому +1

      @@PhysicsNinja Oh just read it. I got it now. The Vmax equation is undefined for a 45° angle and mu = 1. But, by being undefined, that means there is no max speed, the body can go infinitely fast and it is not going to slide. In other words, the friction force will never reach its maximum possible value (mu * N). Thanks!

    • @PhysicsNinja
      @PhysicsNinja  4 роки тому +1

      @@robertosabinospina1066 you got it

  • @lavenderblues
    @lavenderblues 5 років тому +3

    what if theta was 45 degrees and the coefficient was 1

    • @PhysicsNinja
      @PhysicsNinja  5 років тому +4

      Great question. The equation says that the max speed tends toward infinity, however that equation only holds if the denominator is greater than zero. The problem with this limit can be seen if you look at Newton's laws in this limit. You see that the perpendicular component of the Normal and the perpendicular component of the friction cancel out which means we are left with only the weight in this direction.....but that means that the forces can't equal to zero in this limit - mathematically they can if the Normal force is infinite. If the normal force is really big you would need an infinitely strong ramp or tires and this is where the simple picture breaks down. In the limit of mu=1 and the angle approaches 45 degrees it means you can go really fast!!

    • @lavenderblues
      @lavenderblues 5 років тому +1

      Physics Ninja thank you!

  • @hallief8390
    @hallief8390 4 роки тому

    Can the N you found in the end be used for both slow and fast case?

  • @carloscarreon2278
    @carloscarreon2278 Рік тому +1

    awesome!

  • @uzumakinaruto9172
    @uzumakinaruto9172 4 роки тому

    I did a question in which I had to calculate max and min velocity. The value of min velocity came out to be a complex number. What does it mean in physical world?

    • @ProfessorEstrada
      @ProfessorEstrada 5 місяців тому

      Interesting question! First of all, congratulations for the video. It's amazing! About your question, really, 1-tg33º is negative, so, we can't calculate the minimum speed. Not really, though, I think the minimum speed, in this case, is zero. In this case, we can't use the maximum static friction coeficient, 0,7. We need to use a little less, so that we won't have x acceleration (neither y acceleration), so, the speed is zero. In the first equation, the second membre will be zero, instead of mv^2/R, so that u=tg33º=0,65 (less than 0,7, ok?!). In this case, we won't have the maximum static friction, but this is how static friction works: it increases until the maximum, assuming all the values between 0 and u_s.
      In the same way, if 1-utg(theta)

  • @Glacial777
    @Glacial777 Рік тому +1

    this video fye

  • @nilphilodox5759
    @nilphilodox5759 3 роки тому +1

    2:39 how do you know that?

    • @geirha75
      @geirha75 11 місяців тому

      The car drives in a curve or a perfect circle. We know that we because we have defined/assumed that.

  • @reneegiragosian959
    @reneegiragosian959 3 роки тому

    Oh my god thank you

  • @fabihaareeba9657
    @fabihaareeba9657 3 роки тому

    LOVE THISSS!!!!!!!!

  • @coachtofu412
    @coachtofu412 4 роки тому +1

    For Min speed , a negative Speed🤔?

    • @PhysicsNinja
      @PhysicsNinja  4 роки тому

      The expression will never be negative, it would slide down first. sin(theta) is always greater than >us*cos(theta)

    • @coachtofu412
      @coachtofu412 4 роки тому

      @@PhysicsNinja i tried with a degree of 15 for a problem, i come to the same formulas , the max speed Is ok , but when i try with Min speed the numerator became negative rg(sin 15 - 0.5 cos 15)

    • @PhysicsNinja
      @PhysicsNinja  4 роки тому

      @@coachtofu412 That means the minimum speed is 0! The object doesn't have to move in a circle and it will remain on the ramp and not slide down.

    • @PhysicsNinja
      @PhysicsNinja  4 роки тому

      The force of friction is more than enough to hold up the object.

    • @coachtofu412
      @coachtofu412 4 роки тому +1

      @@PhysicsNinja finally i find an answer, love you man

  • @techzone9241
    @techzone9241 3 роки тому +1

    10q sir

  • @ibrahimelzein6288
    @ibrahimelzein6288 2 роки тому +1

    ❤️❤️❤️❤️❤️❤️

  • @sentientarugula2884
    @sentientarugula2884 4 роки тому +1

    gooodeo viiiideo

  • @adamsansom2922
    @adamsansom2922 3 роки тому

    The calculations are fine as far as they go but this cannot be compared to reality as you try to do at the end. The reason is that you have ignored the aerodynamic downforce that is generated by the cars themselves, which itself is dependent on the square of speed.