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Attach the DFS and LGA in Combination
The DFS (Dual-Range Force Sensor) and LGA (Low-g Accelerometer) can be used
simultaneously using the same procedures.
Wireless Dynamics Sensor System
To attach a Wireless Dynamics Sensor System (WDSS), remove and store the two
silver pins for the Dual-Range Force Sensor. Place the WDSS on the top surface of
the cart, and use the large mounting bolt to secure the sensor to the cart.
General Tips for the Vernier Dynamics Cart and Track System
Do not install the magnets unless you know you want to use them. They will
interfere if you perform an experiment with a force sensor riding on the cart, since
the force sensor will then not read the total force acting on the cart.
The magnets are designed for fairly gentle collisions. If the cart is moving too
quickly, the magnetic forces may cause the cart to jump off the track to the side. If
this happens, use a lower initial velocity for the cart.
Keep the track clean; if it is dirty the carts will not roll smoothly.
Use lower speeds and lower inclines than you might initially choose; the physics
is the same and students will have more time to observe what is happening.
Attach the track feet, sliding at least one in about 30 cm before inserting the
Motion Detector Bracket.
Study the Motion Detector Bracket photo carefully and note that the bracket is
attached to the underside of the track. A common error is to attach the bracket to
the top slot on the track.
Suggested Experiments
The Vernier Motion Encoder System can be used wherever a Motion Detector could
have been used with a cart and track. The encoder depends on the presence of the
track, so that
only
cart and track experiments can be performed.
Measure Cart Acceleration
The basic motion of a cart on a ramp can be studied. For example, perform
Experiment 3 from
Physics with Vernier
, “Cart on a Ramp.” Or, repeat Galileo’s
experiment of determining
g
using an object and a ramp. This is Experiment 4,
“Determining
g
on an Incline,” from
Physics with Vernier
.
Newton’s Second Law
Use a force sensor on the encoder cart to record both applied force and acceleration.
The two will be proportional.
10
Or, set up a half-Atwood machine with a hanging mass and a pulley at the track end
opposite the receiver. Measure the acceleration of the encoder cart as a function of
the hanging mass.
Measure Fan Cart Acceleration
Add an Encoder Fan Cart (order code CART-FEC) to observe the motion of a cart
under constant thrust.
Measure Cart Acceleration with Friction
Add a Friction Pad (order code DTS-PAD) to the encoder cart and observe the
motion of the cart with varying frictional forces.
Momentum-Impulse
Add a force sensor and a Bumper-Launcher Kit (order code BLK) to observe the
relationship between momentum and impulse. Find the impulse by integrating under
a force
vs.
time graph.
Conservation of Energy
Use two Vernier Motion Encoder Systems to observe a change in energy due to a
collision between two carts.
Conservation of Momentum
Use two Vernier Motion Encoder Systems to observe a change in momentum due to
a collision between two carts. Try different kinds of collision: elastic, inelastic,
totally inelastic.
Products Related to the Vernier Dynamics Cart and Track
System with Motion Encoder
Vernier Dynamics Cart and Track System (order code DTS)
Vernier Dynamics System is a low-friction 1.2 m track and optics bench
combination designed for kinematics, dynamics, and optics experiments. It includes
two carts. The hardware does not include the Motion Encoder Cart and Receiver.
Vernier Dynamics Cart and Track System with Long Track (order code DTS-
LONG)
The long version of the Vernier Dynamics System includes a 2.2 m track instead of
the 1.2 standard track.
Track (order code TRACK)
The Combination 1.2 m Track/Optics Bench comes with the Encoder System Strip
installed.
Replacement Parts
Motion Encoder Receiver (order code MEC-BTD)
The receiver attaches to the end of the track and connects to an interface, such as a
LabQuest 2.
Motion Encoder Cart (order code CART-MEC)
This is the complete Motion Encoder Cart, with no assembly required.
