®
Model No. ME-9491
Suggested Experiments
1
3
3.
Vary the mass of the Fan Accessory by placing or removing the slugs or batteries
in the storage rack.
Suggested Experiments
1
Experiment #1:
Measure the acceleration of the cart using the Motion Sensor, Smart
Pulley or Tape Timer. Vary the mass of the Fan Accessory or the speed of the propel-
ler and repeat (Figure 3)
.
Experiment #2:
Determine the force of the fan by connecting the cart to a mass that
hangs over a pulley. Adjust the hanging mass until the cart doesn’t move. Vary the fan
speed and repeat (Figure 4)
.-
Alternative method:
Use a spring scale to determine the fan’s force at three different
propeller speeds (Figure 5)
.
1
For a discussion of fan cart experiments, refer to Robert A. Morse, “Constant Accelera-
tion Experiments with a Fan-Driven Dynamics Cart,”
The Physics Teacher
, October, 1993,
pp. 436-438.
Figure 3. Measuring the acceleration of the cart.
air flow
force
V
cart
Dynamics Track
Motion Sensor
rubber bands
Fan Accessory
Figure 4. Determining the fan’s force (method 1).
air flow
hanging mass
Figure 5. Determining the fan’s force (method 2).
spring scale
force
air flow
Note:
To prevent the Fan Acces-
sory from popping off the cart dur-
ing a collision with a wall or End
Stop, secure it to the cart with the
included rubber bands as shown in
Figure 3.
