Up and Down

By: Sammy McQueen, Andrea Huber and Sarah Bos

Experiment

● Place CBR on ground directly below a spring mounted on desk. Drop spring so it falls straight down towards sensor and bounces back up (moving closer then farther from sensor). Extra movements near sensor will disrupt data collection.

● Collected data should create sinusoidal graph.

Data/Graph

0 1.783.57

T(sec)

Dis

t.(ft)

.

4293

.4

3.4

307

Regression Equation

Y=5.31X10-4sin(100.93(X+2.42))+.43

● amplitude● b value of period formula● horizontal shift● vertical shift

Amplitude

The amplitude is how far the spring goes in either direction.

Amplitude: 5.31x10-4

To change the amplitude: You could start it closer to the CBR, or also

add more weight to the spring.

Period

The Period is how long it takes for a spring to cycle from the bottom to the top

To find the Period we used 360/b360/100.93

Period= 3.57 seconds

Extensions-Replacing the Spring with a Pendulum

● If we were asked to replace the spring with a pendulum we would mount the CBR on the wall facing the pendulum. Then, start with the pendulum ½ feet away from the CBR and letting go of the pendulum.

Additional Examples of Periodic Functions

● The orbiting of the moon around the earth is also a periodic function, it repeats itself every 24 hours.

● A car around a race track is another periodic function because it passes the same place every lap. The course of the track is the independent variable and the speed of the racecar is the dependent variable

Write up● Problems collecting data - it took

several tries before we had the spring lined up with the CBR and a smooth drop at the same time.

● If we were to do this lab again, we should take our technique to an area with less noise for the CBR to pick up on during the experiment.