Question

DESPERATE - MEDAL WILL BE AWARDED- explanation please if you are given a graph with points how do you estimate the velocity of a particle when x= any number link is provided

Answer 1

http://www.cambridge.edu.au/go/download/?f=10605&t=1934 page 528 queston 8 d

Answer 2

You know that the velocity is the rate of change of position (x) over time (t). If the graph is x versus time (t), then the rate of change is simply the slope. If you want to find the velocity at a given position x, find where the line is at x, then find the slope.
You can find the slope m of a graph by:
\[m=\frac{\Delta x}{\Delta t}=\frac{x_2-x_1}{t_2-t_1}\]
Where x2 is the x-value (height) of your right point, x_1 is the x-value of your left point, t_2 is the t-value (time) of your right point, and t_1 is the t-value of your left point