Investigation of the rolling motion of a hollow cylinder using a smartphone’s digital compass

Abstract

This study used a smartphone's digital compass to observe the rolling motion of a hollow cylinder on an inclined plane. The smartphone (an iPhone 4s) was attached to the end of one side of a hollow cylinder to record the experimental data using the SensorLog application. In the experiment, the change of angular position was measured by the smartphone's digital compass. The obtained results were then analyzed and calculated to determine various parameters of the motion, such as the angular velocity, angular acceleration, critical angle, and coefficient of static friction. The experimental results obtained from using the digital compass were compared with those obtained from using a gyroscope sensor. Moreover, the results obtained from both sensors were consistent with the calculations for the rolling motion. We expect that this experiment will be valuable for use in physics laboratories.

Advanced tools for smartphone-based experiments: phyphox

“…A common one is the phone in a pendulum setup [6,7,8]. Other interesting examples are most experiments that measure centripetal acceleration by rotating a phone [9,10,11] (for example in a salad spinner or on a record player) and experiments in which the phone is placed in a tire or a roll to measure its velocity [12,13,14].…”

Feasibility of Smartphone Camera Utilization and Power Point-based Video Analyzer on Kinematic Motion Experiment: An Inexpensive Method

“…Afterward, the length of reference size which was determined is then measured in the captured video by drawing a reference line ( ) as shown in Figure 3. By comparing the line length with the actual reference size, the calibration constant is then obtained using equation (1). 1This constant will be used to collect the actual ball position   h from the measured position at video  …”

“…Nowadays, misconceptions become one of a problem in physics learning [1,2]. For example, on kinematics subjects, students think if a free-fall motion is not only caused by gravitational acceleration, or another example, there is acceleration on the horizontal motion in projectile motion case.…”

“…In overcoming the problems, experiments can be a solution due to the direct observation of physics phenomena by students [3]. So, they can relate the phenomena to the theory and then increase their understanding [1][2][3][4].…”

“…Various devices have been used to make an easy understanding demonstration tool, such as computer-based instrumentation tool [5], game controller [1][2], camera [6][7][8][9][10][11], and smartphones [1][2][12][13]. Among the others, smartphones are widely used because it has been embedded with various sensors [1][2]14]. The smartphone not only used on academics but also for other applications like spectroscopy analysis, psychiatric and medical examination, and also health monitoring [14].…”