Starting from A, Paheli moves along a rectangular path ABCD as shown in Figure 13.7. She takes 2 minutes to travel each side. Plot a distance-time graph and explain whether the motion is uniform or non-uniform.

Question

Philoid · Accepted Answer

Here is a graph between distance and time:

x-axis represents time in minutes and y-axis represent distance in the meter.

Paheli starts from position A and go to point B in 2 min so distance cover is 8 m.We mark point (A) 2 min on axis and point (C) on y-axis then we draw a line passing to pt(A) parallel to the y-axis and one more line passing to pt(C) parallel to the x-axis. Where the two-line interest will be marked as pt(B). Join the pt(B) and pt(O). This line represents a graph of one side

Similarly, we do for all the side.

Speed of Paheli will moving alongside AB is (distance/time) = () m/min = 4 m/min

Here the unit is meter/minute.

Speed along side BC is = = 3 m/min

Speed alongside CD is = = 4 m/min

Speed along side DA is = = 3 m/min

So, we find that Paheli speed is not the same in the whole journey.

Motion is nonuniform.

Nonuniform can also be found from the distance-time graph, here line is not straight so it is non-uniform motion.