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course phy 201
01-01 2:30
Truck overtakes car
You used a combination of three tracks to simulate the problem in which a car passes before I pull out in my truck.
Insert a copy of your data here, along with any previously submitted work you wish to include:
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car moving at a constant velocity of 7 cm/s; released 4.3 cm above a 30 cm ramp
truck accel at 24 cm/s with initial velocity of 0 cm/s and final velocity of 48 cm/s; truck travels 60 cm in 2.5 sec.
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Explain how you positioned the ball representing the truck, the ball representing the car, and how you timed the release of each.
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ball representing the truck was positioned at the end of a 60 cm ramp. timed by stopwatch from release.
ball representing car was released 4.3 cm above the 2nd 30 cm ramp (34.3 cm total). timed at beginning of 30 cm ramp.
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7 cm/s isn't raw data, it's information calculated from raw data related to change in position and change in clock time. You need to report the raw data from which you got 7 cm/s.
60 cm and 2.5 sec would be raw data.
After reporting your raw data you would then show how it is used to get things like 24 cm/s, 48 cm/s, etc. (these quantities are correct, incidentally; that is, they do follow from your raw data)..
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According to your data what was the velocity of the ball representing the car at the instant it passed the position of the ball representing the truck?
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velocity of car was a constant 7 cm/s
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According to your data what was the acceleration of the ball representing the truck?
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accel was 24 cm/s
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Acceleration is rate of change of velocity with respect to clock time.
24 cm/s is your average rate of change of position with respect to clock time, i.e., your average velocity. This is not to be confused with average acceleration.
You still need to calculate average acceleration.
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According to your observations, what were the positions of the two balls when their velocities matched?
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approx 10 cm from end of the 2nd 30 cm ramp
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According to your previously calculated accelerations and velocities, what were the positions of the two balls when their velocities matched?
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truck
v0=0
a=24 cm/s
vf=48cm/s
Vave=(0cm/s+48cm/s)/2=24cm/s
`dt=(48cm/s-0cm/s)/(24cm/s)=2sec
`ds=((48cm/s+0cm/s)/2)*2sec=48 cm
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Right idea, but the acceleration isn't 24 cm/s. The number isn't right, and the units aren't right.
If you get the correct acceleration this will work.
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According to your observations, at what position did the ball representing the truck overtake the ball representing the car?
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approx 10 cm to the end of the 2nd 30 cm ramp.
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According to your previously calculated velocities and accelerations, at what position should the ball representing the truck overtake the ball representing the car?
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`ds=((48cm/s+0cm/s)/2)*2sec=48cm
truck will overtake car after 48 cm
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Not bad, but be sure to see my notes about reporting data and include the data you used to get that 7 cm/s.
You do need to refigure your acceleration and the later result that depends on it.
&#Please see my notes and, unless my notes indicate that revision is optional, submit a copy of this document with revisions and/or questions, and mark your insertions with &&&& (please mark each insertion at the beginning and at the end).
Be sure to include the entire document, including my notes.
If my notes indicate that revision is optional, use your own judgement as to whether a revision will benefit you. &#
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