determining the acceleration due to gravity lab

DETERMINING THE ACCELERATION DUE TO GRAVITY LAB FREE

In March of 1999, when the American Physical Society had its centennial celebration, it provided a viewgraph (for the use of a group of centennial speakers-I was one) that was entitled “Throughout the Year we are Celebrating ALL (capitalization theirs) Areas of Physics” ( Fig. In spite of the importance of this field to scientific progress, precision measurement science is often overlooked. The reason is that this area of physics is not just a collection of accurate measurements rather it is an area of fundamental importance that involves measurement science applied to a broad range of related experiments and therefore no “s.” I also want to reflect on precision measurement-not, the reader needs to understand, precision measurements-by using these various measurements as examples of experiments of this type. The final measurement in this group of related experiments was a test of the inverse-square law of gravitation on the scale of meters to kilometers. The other equivalence test that I will mention was a result of the lunar laser-ranging experiment.

DETERMINING THE ACCELERATION DUE TO GRAVITY LAB FREE

One experiment that I will describe tested the equivalence of free fall for different masses in response to local attracting matter (the Earth) rather than to more distant matter (the Sun, which has been used in recent equivalence tests). Reprinted by permission of Universal Press Syndicate. In your own experiments, you can collect data from shorter or longer distances.Gravity can be arbitrary. Use your own data to calculate the acceleration of the flashlight you drop. The time it takes to make that change is 0.33 sĪcceleration = (3.33 m/s – 0 m/s) / 0.33 s = 10 m/s 2 In our case, at time 0.297 to 0.33 s (time = 0.033 s), the distance traveled is from 0.4 m to 0.51 m (distance = 0.11 m). V initial is the flashlight’s velocity just before it’s dropped, or 0 m/s V final is the velocity of the light at the end of the drop. Here’s an example using our data (see the table above): If your flashlight leaves a streak of light, only record the location at the bottom of the streak (the streak is a 1/30 th of a second record of the light's fall).Ĭalculate the acceleration due to gravityĪcceleration describes how fast the rate of something changes.Īcceleration = ( V final – V initial) / the time to make this change Notice that, during the first few steps, the flashlight doesn’t fall very much. Now, step by step, record the distance in meters dropped and the corresponding time of the flashlight’s fall. The frame you’re now at is time 0s and distance 0m.)

(Note that frame-by-frame players usually let you move forward or backward via arrow keys. That means each frame will add an additional 0.033 seconds.ĭistance Data: In your video player, find the frame just before your flashlight drops. Time Data: Since your camera records 30 frames a second, each frame represents only 1/30 of a second, or about 0.033 seconds. Label the columns “Time in seconds” and “Distance in meters.” (See the sample table below.) Make a table with two columns to record your data. Redo it if you didn’t get a clear view of your flashlight’s light falling straight down. Digital video is easy to erase and reshoot. Have someone else film the drop with a digital camera (in HD at standard 30 frames per second).Ĭheck your video to make sure you got the shot. If possible, use only one finger to hold the flashlight still until the time of release. Place the light as close to the 0 cm mark as possible and against the measuring tape. Make sure your flashlight is on a non-blinking setting. Turn on the flashlight and point it upwards. Have one partner stand next to the measuring tape.

Determining the acceleration due to gravity lab