Angular Momentum - Clay Puck and Stick Collision

Link to previous video: • Conservation of Angula...
Physics Ninja looks at a collision problem involving conservation of angular momentum. Linear and angular momentum conservation are used to solve for the velocity of the center of mass and the angular velocity after the collision. The kinetic energy before and after the collision are compared.

[@enricolucarelli816]

Finally someone who dares to remove any pivot point!😁 Thank you! 👏👏👏👏 It is interesting to notice that there is a point, 5L/12 above the CG, that will start moving along a cycloid. Thus, we can use a similar calculation to find out where to hold the handle of a hammer when hitting a nail, in order to minimize the impact on the wrist 👍

[@arkajyoti6950]

Man i cant thank you enough for your efforts in making these detailed videos for us. Love your dedication in explaining every minor concepts while solving problems 🙏❤

[@ashurbanipal5193]

you're very good teacher. your style to describe topics is very clear / understandable. you are helping too much. thanks you for your videos.

[@InfuriatedFrog]

Found your channel and now I’m loving physics even more than I already did

[@PhysicsNinja]

Welcome aboard!

[@tozaisusovac6842]

Thanks a ton, I was a bit stuck on how to formulate the proper equation, I forgot to account for the puck´s moment of inertia :)

[@sarthakghoshrollno.2276]

I love physics very much, specially mechanics, and i found this video very useful. Thanls for this interactive style, that's beautiful.

[@PhysicsNinja]

Thank you so much!

[@izzygrandic]

you are a great instructor!

[@PhysicsNinja]

Thank you so much

[@EfeKaanikizoglu]

thanks, you helped me a lot

[@mikemaas8134]

Great explanation, thanks! I would just suggest not using capital L for both length and angular momentum in the derivation. Can be a bit confusing for students new to the topic.

[@samsara2024]

Can you do the same exersice in 3D with two rigid bodies moving in 3D space, please?

[@MuhFerdiansyahscience]

Good

[@fredthecoder1289]

Ninja, good video. But I ma not sure about the sin(90) justification. Isn't theta the angle between the linear velocity vector and the position vector from the axis of rotation to the combined system's centre of mass ? If the combined mass is rotating about the system centre of mass, won't 'd' be just zero?

[@PhysicsNinja]

Yes, that is what i meant to say but i said perpendicular to the axis. It's the angle between the velocity vector and the vector going from the axis of rotation to the point of impact. Still 90deg.

[@user-sc7hr9dg3z]

👍👍👍👍👍👍👍

[@Test-iv4pm]

What happens to the energy that is not conserved from Ki to Kf?

[@PhysicsNinja]

Dissipated as heat

[@CakeHopper1]

​@@PhysicsNinja But the problem assumes it's a perfect rigid body collision with no energy lost. Why can energy be lost in a fictional scenario? Is energy always lost when a ball hits a rod?

[@Ninjamanguy732]

Isn’t gravity and the normal force from the ground considered external forces? Why are they not considered when evaluating if linear momentum is conserved?

[@PhysicsNinja]

Those are considered perpendicular to the page.

[@marionoyola1071]

They balanced out because they are y-forces

[@user-px5pj7ux5k]

hope you put some specific variables example😊

[@bluefoxf5963]

Good