Question

Given $x-t$ graph represent the motion of an object. Match the Column I (parts of graph) with Column II (representation) and select the correct answer from the codes given below.

Column I		Column II
A	Part $O A$ of graph	1	Positive velocity
B	Part $A B$ of graph	2	Object at rest
C	Part $B C$ of graph	3	Negative velocity
D	Point $A$ in the graph	4	Change in direction of motion

• A. $A - (1), B - (2), C - (3), D - (4)$
• B. $A - (1), B - (3), C - (2), D - (4)$
• C. $A - (2), B - (1), C - (3), D - (4)$
• D. $A - (4), B - (3), C - (2), D - (1)$

Answer 1

Answer: (B)

In $x-t$ graph, $O A \rightarrow$ Positive slope $\rightarrow$ Positive velocity
$A B \rightarrow$ Negative slope $\rightarrow$ Negative velocity
$B C \rightarrow$ Zero slope $\rightarrow$ Object at rest

At point $A$, there is a change in sign of velocity, hence the direction of motion must have changed at $A$.
Hence, $A \rightarrow 1, B \rightarrow 3, C \rightarrow 2$ and $D \rightarrow 4$.