Determining instantaneous velocity and average velocity using a graph.

Crescent

The position of a rabbit along a straight tunnel as a function of time is plotted in Fig. 2-26.
Here's the figure:
http://www.webassign.net/giancoli5/2_26.gif

Determine its instantaneous velocity at the following times.
(a) t = 5.0 s
(b) t = 30.0 s

Determine its average velocity between the following times.
(c) t = 0 and t = 5.0 s
(d) t = 25.0 s and t = 30.0 s
(e) t = 45.0 s and t = 50.0 s


a) I tried to find the slope of the straight line through [0,20] seconds by taking two points in it and take delta x / delta t

b) I drrew a tangent line to the curve at t = 30 then find its slope.


For c , d , & e the avg v is:

(Xfinal - Xinitial)/(t final - t initial)

but still, I could not find an answer for any of them. It seems as if nothing is working.

tiny-tim

Hi Crescent! Welcome to PF!

Show us what you've tried, and where you're stuck, and then we'll know how to help!

djeitnstine

Where is your working?