This week we will be learning about Newton's Universal Law of Gravitation. The formula he discovered about the gravitation force between two masses is=/d^2, where M is mass 1, m is mass 2, and d is the center of mass distances between the two masses. G is the gravitational constant. Although Newton discovered the formula, he didn't know the value of G. Henry Cavendish was the first to measure G. Once this gravitational constant was discovered we were able to determine the mass of the Earth as well as its density. Here is a (2:00) video describing the Cavendish experiment and its importance.

https://www.youtube.com/watch?v=hKTNMNxW5tQ

The next 3 videos are actual experiments that have been conducted that you can observe.

Cavendish Experiment (1:50)(https://www.youtube.com/watch?v=Ym6nlwvQZnE&feature=youtu.be )

Cavendish Experiment animated (3:27)(https://www.youtube.com/watch?v=4JGgYjJhGEE )

Gen Gen is a student who submitted this as an assignment. It's excellently explained.)

Gen Gen's Cavendish Experiment (6:51)(https://www.youtube.com/watch?v=jkjqrlYOW_0 )

Bennett's Cavendish Experiment (15:17)(https://www.youtube.com/watch?v=Mcg2h--JDv4&feature=youtu.be )

Describe the Cavendish Experiment and explain how it allows us to determine G. Be detailed to demonstrate you understand the experiment and its results. In the experimental videos above there is a source of error that was unavoidable. What is it?Explain how come this is a source of error and how it affects the results. (Note: Please notice that it is NOT a human error. When looking for experimental errors we are looking for errors that are not easily fixed in our system. How did Cavendish avoid this error? Calculate the percent error between Gen Gen's results and the accepted value of G = 6.673 x 10-11m³/s²kg.

Explain why the ball had to be moved directly underneath the pyramid in the

Cavendish Experiment (1:50)(https://www.youtube.com/watch?v=Ym6nlwvQZnE. )

video. Why didn't the scale recognize the force of attraction when the ball was not directly underneath the pyramid?Based on the information provided in the video as well as being given the mass of the Earth is 5.97 x 1024kg and the radius of the Earth is 6.4 x 106m, calculate the mass of the ball. What assumption(s) are you able to make to solve this problem?(Hint: It has to do with distance.)