Physics Laboratory
Kinematics on an Inclined Plane
Smart TimerTM Laboratory
Objective: In this experiment, you will investigate the velocity of an object as it
undergoes a constant acceleration.
Introduction:
The object is you will use to investigate velocity at a constant acceleration is a ball rolling
down an incline plane. Instead of the usual investigation of velocity as a function of time,
you will measure its velocity as a function of the distance it has traveled from its starting
point.
Procedure:
1. Set up the ramp as shown below. Use books to raise one side of the ramp. Using
masking tape, place three to four metric rulers (with grooves) onto the center of
the ramp. Place the ramp as close to the end of the lab table as possible (about 3-4
cm away from edge is acceptable). Put a photogate somewhere around the 110 cm
mark on the ramp. Add a second photogate to the setup as close to the first
photogate as possible (around 120 cm). Attach the SMART Timer to the SMART
Pulley photogates and turn it on. Record the distance the photogates are apart as
Δd.
Δd = ___________ cm
Photogates 1 & 2
SMART Timer
Ramp Setup
Physics Laboratory
2. Choose Time under Select Measurement on the SMART Timer then select Two
Gates under Select Mode. Now move the ball to a starting point 5 cm above the
midpoint on the ramp. Mark the starting position with a pencil so you will be able
to repeat the run, starting the ball each time from the same point. Hold the ball at
this position using a ruler, pencil, or block of wood. Make sure the timer is not
actively timing. Press the Start/Stop button and release the ball so that it moves
along the ramp and through the photogates. Record the time and distance travelled
in your table. NOTE: Make sure that the ball goes through both photogates (you
will not get a time if it does not)! If the ball is not going through the photogates,
adjust the ramp accordingly.
3. Repeat the trial at least 3 times with the same starting point and average the times
you measure.
4. Move the ball to positions 10, 15, 20…40 cm from the midpoint, repeat steps 3-4.
5. Erase all pencil marks from the ramp after all the data has been collected.
6. For each distance from the midpoint between the photogates, calculate the final
velocity of the ball by dividing d by your average time.
7. Construct a final velocity versus distance travelled graph, with the distance on
the x-axis.
Physics Laboratory
Data (insert units for each column)
Distance
Travelled
(ball’s start
to finish)
Time 1
Time 2
Time 3
Average
Time
Final
Velocity
(d/average
time)