Question

7. You start to walk toward the east towards home at a constant speed of 4 km/hr. At the same time, Someone else leaves your home driving west at 28 km/hr. The total distance for your walk is 3.2 km. a. Draw a position-time graph that shows the motion of you and the other person. b. From the graph, determine how long you will travel before you meet the other person. c. You do NOT need a trend line for this graph but you do need to have the other required parts.

Answer 1

A) position time graph for both is shown

here one of the graph is of lesser slope which means it is moving with less speed while other have larger slope which shows larger speed

At one point they intersects which is the point where they both will meet

B) Let the two will meet after time "t"

now we can say that

if they both will meet after time "t"

then the total distance moved by you and other person will be same as the distance between you and home

so it is given as

$v_1t + v_2t = d$

$4*t + 28*t = 3.2 km$

$t = \frac{3.2}{32} = 0.1 hr$

so they will meet after t = 6 min

so from position time graph we can see that two will meet after t = 6 min where at this position two graphs will intersect