zap123
Im doing a project on how to learn how to use a ticker timer and
investigate acceleration using a ticker time .

Equipment:
Car
String
Weights
Clamp x2
Ticker Timer
Strand of paper

Heres my results
Distance Seconds Distance from 0
5.3 0.1 dot 1 5.3cm
another 6.2 0.2 dot 2 11.5cm
another 10.1 0.3 dot 3 21.6 cm
another 12.5 0.4 dot 4 34.1 cm
another 15.1 0.5 dot 5 49.2cm

My question is
Calculate the average acceleration? (How u do that?)
Describe what each graph is telling you. Point out that parts on graph
that represent acceleration and constant speed? CAN SOMEONE ANSWER MY QUESTIONS??? PLEASE???
zap123
CAN ANYONE HELP ME????
Strider
To make it easier to see, I first graphed it in excel.

1. The trolly would stop accelerating if the velocity would stop changing, or on the graph, the line would become straight at a 45 degree angle to the base. I can't really tell without more measurements, but it looks like towards the end, it does seem like it stopped accelerating.

2. First of all you need to find the change in velocity before you can find the acceleration. I assume you don't have to come up with an equation to fit your data points, so I don't think you'll need the differential equations, but I'll throw them in anyways. They are useful if you need to find the exact velocity or acceleration at a certain time, not just an average like what I'll be doing below.

Velocity = change in distance / change in time
or
v=d/dt(distance) where t=time in sec (d/dt means take the derivative of equation with respect to variable 't' which is time in our case)

Acceleration = change in velocity / change in time
or
a=d/dt(velocity)

To find the velocity of each time interval we'll use this equation instead of using derivatives because your points are taken at each discreet time intervals. Keep in mind that this is an average velocity not the exact velocity, but since the time interval is 0.1 sec, it should be a good approximation. It doesn't mean that right at zero second, the trolly is going 53cm/sec because right at 0sec, it is going 0cm/sec.

V=(distance final - distance initial) / (time final - time initial)

Thus for the first sample:
V0=( 5.3cm - 0cm ) / ( 0.1sec - 0sec)
V0= 53 cm/sec

For the second sample:
V1=( 11.5cm - 5.3cm ) / (0.2sec - 0.1sec)
V1=62 cm/sec

and so fourth for V2, V3, and V4

It works out that:
V0= 53 cm/sec
V1= 62 cm/sec
V2= 101 cm/sec
V3= 125 cm/sec
V4= 151 cm/sec
(verify for yourself)

Now that you have the velocities at each time interval, you can find the acceleration:
Thus A= (velocity final - velcoity initial) / (time final - time initial)

A0=(53 cm/sec - 0cm/sec) / (0.1sec - 0sec)
A0=530 cm/sec^2

The rest I'll leave up to you to do.

3. To find the average, it is easy, just add up all the acceleration points then divide by the number of points you added up.

Ave = (K1+K2+...+Kn)/n where n is an integer
Ex:
Ave = (2+3+1)/3 = 2

4. The graph is telling you the distance traveled compared to the amount of time it took to travel that distance. From this graph acceleration occurs when the distance vs time rises or decreases . If the graph starts to become linear ( the line makes a 45 degree angle to the base of the graph ) then it has stopped accelerating and has constant speed. This is what seems to be happening towards the end of your measurements as friction and drag starts to counter the acceleration due to gravity.

Hope this helps a little. What's this project for?
Guest_anonymous
QUOTE (zap123+Aug 27 2005, 05:39 AM)
CAN ANYONE HELP ME????

what is a ticker timer????!!
bum
its kinda hard to explain...... a ticket timer is a device that shows how fast an object is going.... you put the "tape" through the ticket timer and then attach it to an object......after the object has stopped you will see "dots" on the paper, this shows how fast the object has travelled.....the closer the dots r together the slower the object travels...the further the dots are apart the faster the object has travelled.....
jessica
QUOTE (bum+Jul 23 2006, 07:57 AM)
its kinda hard to explain...... a ticket timer is a device that shows how fast an object is going.... you put the "tape" through the ticket timer and then attach it to an object......after the object has stopped you will see "dots" on the paper, this shows how fast the object has travelled.....the closer the dots r together the slower the object travels...the further the dots are apart the faster the object has travelled.....

thanks~~ that helped!!!! u rock~~~!!
corey
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What is the point of doing this experiment?