Physics 10 Momentum and Impulse (28 of 30) 2-D Collision Ex.2

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10 жыл бұрын

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In this video I will find velocity final of a 2-dimensional collision, example 2.

Пікірлер: 70

@jandon603 8 жыл бұрын

Thank you for your videos!! Just know that all of my Physics I class, or what's left of it, watch your videos and we all agree that you make sense of EVERYTHING!!! Thanks again!

@gamerxanimexweeb 6 жыл бұрын

idk if it's just me, but it feels very engaging and effective to learn when you watch your teacher make a mistake and see them note and correct it like with 6:42

@sccm100 6 жыл бұрын

I look at the problem, pause, solve it, and check if my answers are right. thanks man! I love practicing using your videos

@fatihsolak4143 5 жыл бұрын

Thanks for everything Mr.Michel.These videos really help a lot.

@TheDespicableD 9 жыл бұрын

Many thanks! Teaching skills are impeccable. The first example in each of video sets guides and helps me understand the theory. I then try to solve the subsequent examples by myself and it really helps!

@Oscar-mt3uf 6 жыл бұрын

Thank you very much Michel, your videos have helped me very much. I struggled to understand my physics class, but with your videos I am able to pause and understand. Your clear handwriting and explanations make everything clear!!

@MichelvanBiezen 6 жыл бұрын

Thank you for the feedback.

@purpohpenguin 8 жыл бұрын

you are the man, thanks for helping me study.

@husseinkhatib9928 7 жыл бұрын

Thank you for the great video!

@ef9374 3 жыл бұрын

Hi Prof., shouldn't VF2 be -2m/sec? VF2 is in the opposite x direction to VF1 which is in the positive x direction. So, both vectors can't have the same direction (or be both positive as denoted by your final values), right? I'm just trying to make sure that i understand these types of problems well. Thanks for answering, in advance.

@MichelvanBiezen 3 жыл бұрын

When working in 2 dimensions, we sometimes calculate the magnitude only and indicate the direction with the arrows. Otherwise to be correct you have to write it in vector components with the x and y direction components separately.

@Sp33dyBeanz 7 жыл бұрын

ya supposed to be cosine 30 degrees for x direction not sin 30

@Danny-og9kr 6 жыл бұрын

6:42

@yangyu2950 7 жыл бұрын

In this video I'm a little confused as to why you can divide everything (both equations) by m, can you explain how that works out? I get why you can do it for the equation on the left but i'm struggling to see why you can cross out the 2m and the m on the right side... got an exam on tuesday i'm studying for. your videos are a major help by the way thank you very much for uploading and taking your time to make these!

@MichelvanBiezen 7 жыл бұрын

Since every term in the equation has the factor "m", we can factor out the m on each side of the equation, and then we can divide both sides of the equation by that same factor. (we can always add, subtract, multiply, or divide both sides of any equation by any number (as long as we do the same thing to both sides of the equation)).

@saharhussein04 4 жыл бұрын

thank you so much for the great video.

@WarriorKazakh 7 жыл бұрын

Could you please make a video with the coefficient of restitution for 2D when the final directions for the two bodies (balls) are not known but the incoming angles are given? Other than that, thank you so much for your videos. I wish we could get certificates from watching your videos as it is only because of you I am now able to do physics very well and not because of my teachers at school. Thank you!

@MichelvanBiezen 7 жыл бұрын

Good idea, we'll work on those next weekend.

@WarriorKazakh 7 жыл бұрын

Awesome! Thank you so much! ;D

@nicholasgalliano8541 Жыл бұрын

Perfect! Thank you very much for your explanation!

@MichelvanBiezen Жыл бұрын

You are welcome! Glad you liked it. 🙂

@yangyu2950 7 жыл бұрын

Its hilarious how many people correct you on these mistakes that you always end up fixing moments later.. like do they just watch, catch the mistake and then turn it off and go onto the next video to repeat the same process?

@celeuse3165 7 жыл бұрын

Thank you for the great video. I solved and resolved this question but got a different answer due to differences in the signs. Why is V2f(cos60) given a negative sign while v2f is in the same direction as v2i?

@MichelvanBiezen 7 жыл бұрын

Per convention, up and to the right are considered positive directions. Down and to the left are considered negative directions. Each momentum component will receive a sign according to those directions.

@celeuse3165 7 жыл бұрын

Michel van Biezen that makes sense to me. And thank you, i have been following your videos, they are very helpful.

@FrankBreen 6 жыл бұрын

Can you write and equation for the final velocity of each object if yo do not know the angles - you do know where the were when they collided

@MichelvanBiezen 6 жыл бұрын

In order to solve for the angles you need to know both of the final velocities.

@FrankBreen 6 жыл бұрын

You are given the initial velocities, the location of the centers of the pucks at collision, the mass and radius of each puck. I need to know the final velocities of each puck to make a computer simulation.

@merciannesiasico839 10 жыл бұрын

hmmmp. i think V1f in the x direction should be V1fcos of theta. Am i right? why is it that it became V1fsin of theta?

@MichelvanBiezen 10 жыл бұрын

Emjay, I am not sure why you are asking the question. Where on the video did I write that the v1fx became equal to v1fsin(theta)?

@MichelvanBiezen 9 жыл бұрын

***** cos (60) = sin (30)

@kyliehelfenbein5029 8 жыл бұрын

at 4:20 it should be cos(30) not sin(30). as you mention above, cos(60) does equal sin(30) but that would be relative to the vertical, not the horizontal.

@user-cr6jo6it6r 8 жыл бұрын

i think you are right man

@brakatsuuu00 7 жыл бұрын

finish the video bro

@carterwilliams7159 7 жыл бұрын

How would you solve this kind of problem given only one angle? Could you do a problem where you have to solve for V1f , V2f, and the angle m2 travels after collision?

@MichelvanBiezen 7 жыл бұрын

If there are 3 unknowns, then you will need some additional information.

@carterwilliams7159 7 жыл бұрын

what additional information would you need? I am given both masses, the final angle of object 1, initial velocity of object 1 and object 2 is at rest

@humairaahmed2737 7 жыл бұрын

Hey! You wrote v1fx=v1fxcos theta and in calculation you have used sin theta. Isn't cos theta correct?

@MichelvanBiezen 7 жыл бұрын

Yes. If you watch the video a little further you will see that I catch the error like you did and then corrected it. Thanks for writing in and letting me know.

@humairaahmed2737 7 жыл бұрын

Michel van Biezen Yep, i found it. I am sorry i didn't notice it first.

@Nioxsae 6 жыл бұрын

Thankyou

@zayanahzamri2996 6 жыл бұрын

hi sir, can you teach me this question, a ball of mass 0.8kg moving at 0.3 m/s collides obliquely with 0.5kg ball moving at 0.5 m/s in the opposite direction. after the collision, the first ball move with speed of 0.15 m/s at theta=30 to its initial direction. what is the velocity of the second ball ? how can we know the velocity because no theta provides for second ball

@MichelvanBiezen 6 жыл бұрын

Since there are two unknowns, the speed of the second ball and its direction after the collision, you will need 2 equations. You will have to solve for the conservation of momentum in both the x and y directions simultaneously.

@zayanahzamri2996 6 жыл бұрын

okay thank you sir

@ariffirdaus3756 9 жыл бұрын

hey michael im sorry for insulting ur hairstyle,anyway u help a lot in my physic test recently

@davidly6456 9 жыл бұрын

How did you get v2f =2 when you isolate the v2f in the equation 2=(1.732)(.866)-0.5v2f wouldnt you get v2f= ((1.732)(.866)-2)/.5 so the answer would be -1m/s

@MichelvanBiezen 9 жыл бұрын

David, You are correct.

@iceverything2000 9 жыл бұрын

Michel van Biezen What are you guys talking about? the equation is not 2=(1.732)(.866)-0.5v2f the equation i 2=(1.732)(.866)(v2f)-0.5v2f, he did it right on the board.

@celeuse3165 7 жыл бұрын

if v2fcos 60 is taken as +ve (of which i do not understand why he made it -ve in the equation) the answer should be V2f=1m/s.

@gopalmali5606 7 жыл бұрын

Hey do you have any videos related Center of Mass

@MichelvanBiezen 7 жыл бұрын

There are 41 videos about the center of mass in this playlist: PHYSICS 14 CENTER OF MASS

@fajeral-haddad3123 9 жыл бұрын

thank you , god bless you

@mrFAhR3Nh3iT 7 жыл бұрын

Professor, can I set my V2o = 0 m/s and my V1o = 5 m/s + 8 m/s? Will this affect my answer?

@MichelvanBiezen 7 жыл бұрын

I would expect it would. Try it and see what happens.

@sniderlw7613 6 жыл бұрын

if some of the kinetic is lost will we have the same answer?

@MichelvanBiezen 6 жыл бұрын

Yes. Energy is typically always lost, but momentum is always conserved.

@timmccoig2811 7 жыл бұрын

Michel, you found the proper components in the free body diagram but messed up on the momentum final in the x direction. The free body diagram states that V1f in the x direction is equal to V1f cos(30 degrees). However (at 4:23) when you were writing out the momentum final in the x direction, you wrote V1fsin(30 degrees) when you were supposed to write V1fcos(30 degrees). This makes this whole video invalid.

@MichelvanBiezen 7 жыл бұрын

Did you watch the rest of the video?

@emilianorodriguez807 7 жыл бұрын

does the positive answer mean m2 is going up not down?

@MichelvanBiezen 7 жыл бұрын

These answers are the magnitudes of the velocities. The arrows indicate the direction of the velocities.

@emilianorodriguez807 7 жыл бұрын

Michel van Biezen, thank you, I see now. Because we took into account the negative direction, we come up with this magnitude. I understand. Thank you Mr. Biezen! You are a great teacher. I'm watching everything on physics and can't wait to get to astronomy! Thank you again.