Lost in the Distance: Navigating Measurement

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    Lost Measurement
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The discussion highlights confusion regarding a problem statement that lacks clarity and essential details, such as specific temperature comparisons and the context for a camera and graph mentioned. Participants note that the expansion coefficients for two metals are referenced without prior explanation. There's also ambiguity about the train's mechanics, particularly regarding its speed and whether it is powered or has brakes engaged. A suggestion is made to assume the train rolls freely downhill to simplify calculations. The overall consensus emphasizes the importance of providing complete information for effective assistance.
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Homework Statement
The following information must be considered: the total mass of the cars and riders is 5225 kg. The train leaves the station at 4.5 m/s and it reaches a speed of 8.0 m/s at the top of the first hill. It takes 16.0 seconds to reach the top. The first hill (on the upwards and the downward side) is angled at 38o. The specific heat capacity of brass and the coefficient of linear expansion of steel are 376 J/kgoC and 12 x 10-6 oC-1, respectively. On the day of analysis, the air temperature is 30.oC. We will also assume that the station track is at ground level. In order to determine the length of track, use a piece of string and the vertical scale outlined on the graph.
With what speed would it reach the bottom of the first hill?
How long will it take for the camera to reach the ground?
Relevant Equations
Any kinematic formulas, Froce formulas and [work, power and energy formulas]
specific formulas were not given with this question.
I tried finding the distance but I later on got confused.
 
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Are you a bot?
 
no? I am sorry if i sounded like a bot lol, i was just trying to write as fast as i can
 
fcici7 said:
no? I am sorry if i sounded like a bot lol, i was just trying to write as fast as i can
The reason for the query was the very disjointed nature of the problem statement.
It specifies expansion coefficients for two metals, but no mention of these in the set up.
One temperature is given, but no other temperature to compare with.
There's a question about a camera, but no prior mention of such.
There's mention of a graph, but it does not instruct you to draw one and you have not attached one.
The train gets faster going up the hill so must be powered by an engine, but we are not told whether it is still engaged, or any brakes applied, on the downhill.

I suggest you assume the train rolls freely downhill. You know its speed at the top and the angle it comes down at. What else do you need to find the speed at the bottom?
 
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Considering the information given, one might just as well ask for the name of the train engineer.
fcici7 said:
. . . i was just trying to write as fast as i can
What's your hurry? It seems that writing fast caused you to skip some of the information that you were given. We cannot help you unless you post all the information that you have.
 
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