I have missed many of my physics classes due to a formidable cold, and thus am in need of guidance on the following questions:
1) Bill is playing in the backyard when his mother asks him to run to the letterbox and collect the mail. Figure 10.16 shows the velocity-time graph for his run to the letterbox.
a. What is Bill's displacement: i. after 8.0 s? ii. between t = 10 s and t = 12 s.
b. How far is the letterbox from where Bill was playing?
c. What is the acceleration at: i. t = 6.0 s? ii. t = 14.0 s?
2) An object starts from rest and travels in a straight line for 5.0 s with a uniform acceleration of 4.0 ms-2. It continues to move with the uniform velocity acquired for a further 12 s and it is finally brought to rest with a
deceleration of 2.5 ms-1.
a. Calculate the distance travelled and the time taken.
b. Draw a velocity-time graph and show how the result for part a could also be obtained from the graph. (If you could simply tell me how this would work, that would be great.)
Thanks in advance.