Horizontal & Vertical Circular Motion with Tension, Worked Examples // HSC Physics

[@seoasadal6652]

These videos are sooo helpful. Thanks!

[@ArchieUplifts]

You're an amazing educator!

[@SaronDawit-sp2zu]

Thank you so much

[@nobunaga5697]

This video helped a lot you🙏

[@learnhscphysics1023]

I have watched a few of your videos and I like your how they are very clear and well explained, though I do have a problem with a couple of assumptions made in this circular motion analysis. In your first example, you have completely ignored the weight force. What then is keeping the the net force in the vertical direction at zero? This needs to be solved the same way you did the second example. Also it is not possible to have vertical uniform circular motion with a rope. Your analysis works fine for the top and the bottom, but if you try it at the sides when the rope is horizontal, the model breaks down. You have mg pointing downwards which means that Fc cannot be directed towards the centre unless the rope applies an upward force on the mass as well as the tension. Obviously ropes cannot do this so you would need a rigid rod. In either of these cases you cannot just ignore or 'wish away' the weight force.

[@ScienceReady]

That's correct. This video simplifies the vector diagrams by making these assumptions. In a real-life scenario, it is not possible to sustain a uniform circular motion in horizontal and vertical orientations. In most cases we can make these assumptions because the mass that is undergoing circular motion is a small (negligible) mass so the associated weight force would also be relatively small.

[@learnhscphysics1023]

@@ScienceReady Hmm... not sure how the weight force can be negligible in the first case since it is more than double the centripetal force Fc = 9 N where weight = 19.6 N.

[@wildepicmovies1044]

HOW WOULD YOU CALCULATE THE MASS

[@lolerishype]

Either manipulate algebraically, or change the problem will give you it.