The Physics Behind Tablecloth Trickery: Newton & Inertia

[AfRoMaNn]

What exactly happens when a tablecloth is pulled out from underneath a table setting, and everything on the table stays put? Newtons laws certainly applies to it but maybe inertia as well?

 

[Dr Lots-o'watts]

Newton's first law and inertia are practically the same. Perhaps worded differently sometimes, but it all refers to the same "phenomena".

You also need a low coefficient of friction between glassware and table cloth, high speed, and preferably low centers of mass for each piece.

 

[vlado_skopsko]

Yes. And the coefficient of friction (The force of friction) does not depend on speed (it is an empirical equation, so it may depend a little), so faster you pull the tablecloth, less time force acts on the glasses and stuff.

 

[dreit]

Yes, my previous physics teacher performed this as a demonstration in class once, and looking back at it now it makes much more sense

 

[PJC01]

I can explain the physics behind the tablecloth trickery using Newton's laws and the concept of inertia. When a tablecloth is pulled out from underneath a table setting, the objects on the table appear to stay in place due to the first law of motion, also known as the law of inertia.

According to Newton's first law, an object at rest will remain at rest and an object in motion will continue to move in a straight line at a constant speed unless acted upon by an external force. In this case, the objects on the table have inertia, which is the tendency of an object to resist changes in its state of motion. Therefore, when the tablecloth is pulled out quickly and smoothly, the objects on the table will continue to move at the same speed and in the same direction as they were before the tablecloth was pulled.

Moreover, the objects on the table also have a large mass compared to the tablecloth, which means they have a greater resistance to changes in their motion. This is why they do not move along with the tablecloth when it is pulled out.

Additionally, the friction between the tablecloth and the objects on the table also plays a crucial role in keeping them in place. The coefficient of friction, which is a measure of how easily the tablecloth can slide over the surface of the table, determines the force needed to move the objects. If the coefficient of friction is high, it will require more force to move the objects, making it harder to pull the tablecloth out without disturbing them.

In conclusion, the tablecloth trickery can be explained by the laws of motion and the concept of inertia. The objects on the table have a tendency to resist changes in their motion, and the friction between the tablecloth and the objects helps to keep them in place. This impressive trick is a perfect example of how we can observe and understand the laws of physics in everyday life.