Answer the following questions about acceleration and velocity–time graphs:
a. (i) Define acceleration and state its SI unit.
b. (ii) Explain, with reason, how the slope of a velocity–time graph represents acceleration.
c. (iii) With neat sketches of straight-line velocity–time graphs, describe what information is conveyed by
(a) a line sloping upward to the right,
(b) a horizontal line, and
(c) a line sloping downward to the right.
d. (iv) Distinguish between uniform and non-uniform acceleration on the basis of the appearance of a velocity–time graph.