What is its velocity equal to zero?

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The discussion focuses on understanding the relationship between position (x(t)) and velocity (v(t)) of a bus over time. It explains that velocity is determined by the change in position over time, with specific cases where the bus's velocity is zero or negative. A horizontal position graph indicates zero velocity, while a steep slope suggests high velocity. The conversation emphasizes the importance of analyzing the slope of the position versus time graph to determine the bus's velocity at different intervals. Overall, the key takeaway is that velocity reflects both speed and direction, with graphical analysis being crucial for understanding motion.
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The function of a bus as a function of time is presented below. At what time is the bus traveling with the greatest velocity? What is its velocity equal to zero? Is there a time where the velocity is negative?
 

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What do you know about the relationship between x(t) and v(t)?
 


I know that V = (Xf-X1)/T, and that x represents the location of an object and t represents time. V represents velocity.
 


The graph in your problem is showing the position of the bus as time passes.

Think about how the position is changing as time moves on, or possibly over specific intervals of time.

Imagine the position line was going across the graph completely horizontally. That would mean the position isn't changing, so the bus must have no velocity.

Now think about if the position changed greatly over a very small period of time. Since the position is changing very quickly, the bus must be moving very quickly.

And remember that velocity is just speed with a direction. If an object is moving forward at 60 miles per hour, that object has a speed of 60 miles per hour, and a positive velocity of 60 miles per hour. If that same object is then going in the opposite direction (backwards) at 60 miles per hour, that object has a speed of 60 miles per hour, and a negative velocity of 60 miles per hour.

Is there a specific part of the problem you're having trouble with? With just the problem and no thoughts with it, it's a bit difficult to figure out where you're at!
 


Has any graphical analysis of the graph of x(t) been mentioned before?

For example, what does the slope of a position v. time graph tell you?
 


Take a point on the graph.
Take second point which is right to the 1st. point as close as possible.

If point #2>(higher)point #1 then velocity positive
If point #2=point #1 then velocity zero
If point #2<(lower)point #1 then velocity negative
 
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