PASCO ME-8930 SMART TIMER - Manual (Page 24)

Smart Timer 012–06734A
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3. Set up the Smart Timer to measure Speed: collision (cm/s). Press to activate the
Smart Timer.
➤ Note: If the flags of both carts do not go through the photogate beams
twice, the Smart Timer will not complete the timing cycle and display velocities
automatically. You will need to push
to stop timing. The completed timing
measurements will be displayed, and the uncompleted measurements will be
registered as 0. Press
or to view the velocities from photogate 2. You can
scroll back and forth between the displayed velocities from photogates 1 and 2
by pressing either of these keys. Press
to reactivate the Speed: collision
(cm/s) mode or to change modes.
4. Perform each of the following completely inelastic collisions:
Equal Masses
a. Place one cart at rest in the middle of the track. Give the other cart an initial
velocity toward the cart at rest.
b. Start both carts at one end of the track. Give the first cart a slow velocity and the
second cart a faster velocity so that the second cart catches the first cart.
Unequal Masses
Put two mass bars in one of the carts so that the mass of one cart (3M) is approximately
three times the mass of the other cart (1M). (Weigh the carts and record the masses in
Table 3.1.)
a. Place the 1M cart at rest in the middle of the track. Give the 3M cart an initial
velocity toward the cart at rest.
b. Start the carts at opposite ends of the track at approximately the same speed
toward each other.
c. Place both carts at one end with the 1M in front of 3M. Give 3M a slightly
greater velocity than 1M so the carts collide between the photogates.
Table 3.1 Data
M
1
M
2
v
e r o f e b 1 tr a c
v
e r o f e b 2 tr a c
v
l a n if
1 l a ir T
2 l a ir T
3 l a ir T
4 l a ir T
5 l a ir T
Note: Do each experiment at least 3 times.