Skip to main content

Get to Know the Math Behind the Cavendish Gravity Experiment

Cavendish Gravity Experiment Math Explained

By Andrew Bennett

Gravity Demo 3.0 Is Underway

This video marks the beginning of my third dive into the Cavendish experiment. Before now, I've created devices that could potentially show the effects of gravitation between small objects. However, I have never eliminated enough sources of uncertainty to make that definitive or to derive a value for G. That is the goal of this summer's physics project.

Math Behind Cavendish Experiment Explained

In this video, I work through the math for determining G from the Cavendish gravity experiment. This math includes the Law of Universal Gravitation, equations for torque (from both a point force and a twisted string), the formula for the period of a torsional oscillator, and some equations for calculating rotational inertia. The end result is an ugly equation that will get us an important value: the Universal Gravitational Constant.



More Info on My Newest Gravity Demo

I plan to spend a large chunk of the summer on this latest design. Before now, this has been more of a classroom demo than an honest attempt at making a measurement for G. I am working toward and expecting much more reliable results with this design, and with it being in an environment that I can control more completely.

If you're interested, please remember to subscribe to my blog and YouTube channel, so you won't miss the updates along the way! I am also using this as an opportunity to improve the production value of my videos and create something that I'm proud of.



I look forward to hearing any ideas and critiques, so don't hesitate to leave a comment below.


Labels

Labels:

Comments

Post a Comment

Popular posts from this blog

Why Do They Do That? The Physics Behind 3 Famous Animal Behaviors

By Amber Bennett Have you ever wondered about the origins of the phrase, "get your ducks in a row"? What about how the "doggy paddle" works or why squirrels are such amazing jumpers? The answers to all of these questions have one thing in common: physics. Keep reading to learn about the science behind these three famous animal behaviors. How Do Squirrels Leap from Branch to Branch? A squirrel leaps through the air.  Photo Credit:  caroline legg ,  CC BY 2.0 , via  Wikimedia Commons The death-defying acrobatic maneuvers performed by squirrels look a lot like parkour tricks. But how do they know how to land tricky jumps between bendy tree branches that move with the wind?  Researchers say  it's a combination of learned behavior (practice makes perfect) and inherited adaptations.  To see what determines how far a squirrel is willing to jump and how the leaps are timed, researchers set up an obstacle course in an artificial forest. Then, they used peanuts ...
Post a Comment
Read more

3 Easy Science Experiments to Do with Your Kids

By Amber Bennett Strong STEM (science, technology, engineering, and math) skills set kids up to succeed both in school and later in life. Encouraging them to be interested in these subjects is easier than you might think, especially if you start when they're young.  Activities that encourage children to be curious and creative will spark a love of learning. Plus, science experiments and other hands-on STEM projects are a fun way to bond with your kids. Here are three easy science experiments that preschoolers and early elementary students will enjoy. 1. Leakproof Plastic Bag A (age 5) doing the leakproof plastic bag experiment. Our preschooler loves to do any experiment that involves water. I can give her a couple of beakers, and she'll happily pour water back and forth between them, especially if I put a few drops of food coloring in each beaker so she can mix the colors.  Another great activity that involves water is the leakproof plastic bag.  All you need are: Large p...
Post a Comment
Read more

All You Need to Know About Torque and the Right-Hand Rules

Photo Credit: Public Domain By Andrew Bennett Torque can be a tricky concept, particularly when we are asked to think of it as a vector. Since torque is a vector, to fully describe the torque caused by a force, we have to give both the magnitude and direction of the torque. The torque describes the ability of a force to change the rotational motion of some object or system. If you were to grab the handle of a door and pull it toward you, you could cause the entire door to rotate.  If you pulled harder (with more force), you could make the door rotate more rapidly (or rather, you would make it have a larger angular acceleration). If you tried to pull the door again, but this time pulled on the hinges, you wouldn't get any rotation. Similarly, if you grabbed the handle and used it to pull directly toward or away from the hinges (to the side, instead of toward yourself), the door's rotation wouldn't change. How Do We Calculate Torque? From this, we can gather that the amount ...
Post a Comment
Read more