PASCO Xplorer-GLX Users’ Guide - Manual (Page 71)

X p l o r e r G L X U s e r s ’ G u i d e 65
Position equal to the Band Spacing. Velocity and Acceleration are calculated
based on the time intervals between the changes in Position.
Picket fences include PASCO parts ME-9377A and ME-9804. Photogate
tape is included with parts ME-6664 and ME-6666.
Smart Pulley (Linear) Use this timer for measuring linear motion with a
Smart Pulley (or a combination of photogate and pulley). The constant, Spoke
Arc Length, equals the circumference of the pulley (in meters) divided by the
number of spokes.
18
The measurements are Position, Velocity, and Acceleration. Each time the photo-
gate is interrupted by a spoke, the timer registers a change in Position equal to the
Spoke Arc Length. Velocity and Acceleration are calculated based on the time
intervals between the changes in Position.
Smart Pulley (Rotational) Use this timer for measuring rotational motion
with a Smart Pulley (or a combination of photogate and pulley). The constant,
Spoke Angle Spacing, equals 360° divided by the number of spokes.
The measurements are (angular) Position, (angular) Velocity and (angular)
Acceleration. Each time the photogate is interrupted by a spoke, the timer regis-
ters a change in angular Position equal to the Spoke Angle Spacing. Angular
Velocity and angular Acceleration are calculated based on the time intervals
between the changes in angle.
Free Fall Adapter Use this timer with PASCO part ME-9207B. The constant,
Height Of Fall, is the distance (in meters) from the release mechanism to the
receptor pad.
The measurements are Time Of Fall and Acceleration.
• Time Of Fall is the time interval starting when the ball is released and ending
when it hits the receptor pad.
• Acceleration is calculated using the formula:
Where a is Acceleration, x is Height Of Fall, and t is Time Of Fall.
Photogate and Pendulum The constant for this timer is Pendulum Width 19 ,
which is the width of the pendulum bob (or whatever part passes through the
photogate).
The measurements are Period and Velocity.
• Period is the time the pendulum takes to complete one cycle of oscillation. A
period data point is recorded every other time the photogate is blocked.
• Velocity is the Pendulum Width divided by the time-in-gate. A velocity data
point is recorded every time the pendulum passes through the photogate. For
more accurate velocity measurements, use a cylindrical (rather than spheri-
cal) pendulum bob.
18 The default value, 0.0150 m, is the
spoke arc length of the inside groove of
the PASCO Super Pulley (part ME-9450)
and similar 10-spoke pulleys.
a
2x
t 2
------ =
19 It is necessary to enter Pendulum
Width only if you are interested in the
velocity of the pendulum bob.