Skip to main content

Cavendish Gravity Experiment: How to Build the Torsion Balance

Cavendish gravity experiment torsion balance
YouTube Screenshot (https://youtu.be/qqyxKSsXX7A)

By Andrew Bennett

In order to replicate the Cavendish gravity experiment and experimentally determine a value for the universal gravitation constant, I built a torsion balance. This revised design is longer than anything I've used before. It also gives me the flexibility to adjust the positions of the attachment points for the wire and the weights.

What Materials Are Included?

PVC pipe is used as the base for the brackets. I heated it with a heat gun, then molded it to the aluminum bar. The weights are currently dumbbell weights with a bottle cap turned into an adapter between the dumbbell mounting holes and the small bolts.

If viewing via email, click here to see the video.

What's Next in the Cavendish Gravity Demo Series?

In the next video, I'll be using the torsion balance as a torsion pendulum to evaluate the torsion constant of the different string and wire options for the Cavendish experiment.  Please be sure to subscribe to my YouTube channel and this blog, so you don't miss the remaining videos about this physics experiment.

Miss a Previous Post?

Part 1: Recreating the Cavendish Gravity Experiment: My First 2 Attempts
Part 2: Get to Know the Math Behind the Cavendish Gravity Experiment
Part 3: Cavendish Gravity Experiment: How to Evaluate and Choose the Materials

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