Question

# M3: Gravity In the Newtonian model for gravity, gravity is a force between two masses, dependent...

M3: Gravity
In the Newtonian model for gravity, gravity is a force between two masses, dependent on the mass of the objects and the square of the distance between the objects’ center of mass. The closer the masses are to each other, the stronger gravity is and the farther they are the weaker it is. Gravity is most commonly understood as the force that makes things fall. Your goal is to understand how the distance an object falls is related to the time it takes to fall.
Theory 1: The time to fall increases linearly with the distance fallen.
Theory 2: The time to fall increases as a power law with distance fallen.
M3 Goal
Create a prediction test to distinguish between the proposed theories and determine which if any are ruled out or supported by your data.
Finding an object to drop
You’ll need an object to drop. To make your experiment more successful you should try to find an object that is heavy, spherical and smaller than about 5 cm. The smaller the better since you will be able to determine its position better. You want it to be heavy and spherical to reduce the impact of air resistance.
Distance
If you have a tape measure, use that. Otherwise, it’ll be time to get creative. Below are listed some “standards” meaning these are objects that have a standard size, and so can be used as a kind of ruler. The uncertainties listed are approximate.
AA Battery length = 5.0 ± 0.1 cm
Diameter of a DVD/CD = 12 ± 0.1 cm
Long side of a standard sheet of paper = 28.0 cm ± 0.1 cm
Long side of a DVD case = 19 ± 0.1 cm (must be single case, not multiple case set)
Width of a USB port = 1.2 ± 0.1 cm
It is recommended you use any of these you have to construct a ruler, marking out multiples or divisions of these lengths onto a sheet of paper.
Also, if you have a smart phone, there are various apps you can use (though you might want to test it with some of the “standards” listed.) OR, if want, you can look up the dimensions of your smart phone and use those.
Time
If you have a computer, tablet or smart phone, you have a clock. On a laptop/desktop you can search your apps for “clock” to find a stopwatch or similar.

#### Earn Coins

Coins can be redeemed for fabulous gifts.