Smartphone accelerometer experiments

The accelerometer measures the acceleration of the phone along three axes, including gravity. In FizziQ it powers the absolute acceleration, linear acceleration, inclinometer, pedometer and G-force instruments. Instruments in FizziQ: absolute acceleration, linear acceleration (X, Y, Z), inclinometer, pedometer, theodolite. Read the glossary entry on the accelerometer.

Each activity below has a protocol, expected results, scientific background, a printable PDF handout and a QR code that opens it directly in the app. FizziQ is free on iOS and Android, needs no account, and shows no advertising.

Activities

Heart rate by accelerometer Middle school 30 min
Students place a smartphone on their chest and use the FizziQ accelerometer to record heartbeat vibrations, comparing heart rate at rest and after exercise.
Centripetal acceleration: spinner High school 35 min
A smartphone spinning inside a salad spinner records acceleration with the FizziQ accelerometer; students verify a = ω²r and assess human g-force tolerance limits.
Atwood machine: Newton's 2nd law High school 30 min
A cart carrying a smartphone is pulled by a hanging mass over a pulley; students measure acceleration with the FizziQ accelerometer and test F = ma by varying mass.
Einstein's equivalence principle High school 30 min
A smartphone accelerometer records rest, uniform motion and free fall; with FizziQ, high school students test Einstein's equivalence principle from the data.
Elevator speed by barometer Middle and high school 15 min
By recording air pressure during a ride, students reconstruct the elevator's altitude profile in FizziQ and calculate its speed from smartphone barometer data.
Sensor accuracy: standard deviation High school 25 min
With the smartphone at rest, students record 20 seconds of accelerometer data and use FizziQ statistics to compute standard deviation and assess sensor precision.
Impact vibrations and seismics Middle school 35 min
Dropping balls from varying heights, middle school students use the smartphone accelerometer as a seismograph in FizziQ to study impact energy and seismic waves.
Free fall: measuring g High school 25 min
Reproducing Galileo's experiment, students drop a cushioned smartphone, time the free fall on the FizziQ accelerometer graph and calculate g from the drop height.
Normal acceleration in rotation High school 25 min
Spinning with a smartphone at arm's length, students record centripetal acceleration with the FizziQ accelerometer and verify a = ω²r. High school physics.
Inclined plane: weight components High school 30 min
High school students place a smartphone on an inclined plane and verify P‖ = mg sin θ and P⊥ = mg cos θ with the FizziQ accelerometer and inclinometer.
Variation of g with latitude High school 30 min
Using the smartphone accelerometer in FizziQ, students measure g precisely, compare results across latitudes and explain why gravity is weaker at the equator.
Pendulum: a = 2gh/r High school 40 min
A smartphone swinging as a pendulum records centripetal acceleration with the FizziQ accelerometer; high school students verify a = 2gh/r and energy conservation.
Variation of g with altitude High school 30 min
During a flight, students record g at ground level and at cruising altitude with the FizziQ smartphone accelerometer and compare the drop with Newton's g = GM/r².
Magnetic inclination and latitude Middle school 30 min
Middle school students record the magnetic dip angle with the smartphone magnetometer and inclinometer in FizziQ Duo mode, then calculate their magnetic latitude.
Tree height with a theodolite Middle school 30 min
Students aim the FizziQ smartphone theodolite at a treetop, measure the elevation angle and apply the tangent formula to calculate the height without climbing.
Pedometer and step detection High school 30 min
Walking 50 steps with the smartphone accelerometer, students read the three-phase signature of each step in FizziQ and compare the peaks with the pedometer count.
Parabolic flight and microgravity High school 25 min
A phone tossed above a mattress records its own free fall: the FizziQ accelerometer on smartphone drops to near zero, showing why astronauts float in a parabola.
Pendulum period: isochronism Middle and high school 35 min
Timing ten oscillations at several amplitudes, students test Galileo's isochronism with FizziQ on smartphone or tablet and compare readings with T = 2π√(L/g).
Straight-line course, no compass Middle school 40 min
Walking 150 steps blindfolded, students hold a heading with the smartphone gyroscope and accelerometer in FizziQ, then judge the sensor drift rovers face on Mars.
G-forces on a roller coaster High school 45 min
A smartphone zipped in a pocket logs G-forces, rotation and pressure during the ride. Back in class, FizziQ data gives the altitude profile and weightless phases.
Moment of inertia of a cylinder High school 30 min
Taped to a rolling cylinder, a phone measures linear and angular acceleration on an incline; FizziQ data lets students calculate the moment of inertia. High school.
Spring constant: k = 4π²m/T² High school 30 min
A smartphone hung from a spring oscillates while FizziQ's accelerometer records the motion; students measure the period and compute the stiffness k = 4π²m/T².
Takeoff speed of an airplane High school 25 min
Record an airliner's acceleration during takeoff with the smartphone accelerometer, then integrate the data in FizziQ to find the takeoff speed. High school.
Uniform rectilinear motion Middle school 25 min
Can you walk at constant velocity? Accelerometer and GPS recordings in the FizziQ smartphone app reveal deviations from uniform rectilinear motion. Middle school.
Linear acceleration: principle Middle school 25 min
Moving a phone along its X axis, middle school students read the linear acceleration graph in FizziQ and link direction of motion, force and sign of acceleration.
Centripetal acceleration: a = ω²R High school 30 min
Spinning with a phone at arm's length, high school students record acceleration with FizziQ's accelerometer, derive ω from timed rotations and verify a = ω²R.
Sun height and seasons Elementary 45-60 min
Using the tablet inclinometer in FizziQ Junior, primary pupils measure solar elevation, compare it with ephemeris data and connect its changes to Earth's tilt.

Other sensors

microphone · magnetometer · barometer · gyroscope · light sensor · camera · GPS · external sensors