Question

Joseph jogs from one end A to the other end B of a straight 300 m road
in 2 minutes 30 seconds and then turns around and jogs 100 m back to
point C in another 1 minute. What are
Joseph’s average speeds and velocities in jogging (a) from A to B and
(b) from A to C?

Answer 1

Total distance travelled (A-B) = 300 m
Total time taken (A-B) = 2mins 30 secs = (2*60 +30) secs = 150 secs
(a) Avg. Speed = 300/150 = 2 m/sec

Total distance = (300+100) m = 400m
Total time = (150 + 60) secs = 210 secs
(b) Avg. Speed = 400/210 = 1.90 m/sec

Answer 2

AnswEr:

Let Joseph Jogs from A to B and back to C as shown.

a.) From A to B distance, displacement = 300 m

Time taken = 2 min 30 sec = 150 s

$\therefore$ $\sf{Average\:Speed:-}$

$\Rightarrow$$\sf{Average\:velocity}$

$\Rightarrow$$\sf\dfrac{300}{150}$ = 2 m/s .

___________________________

b.) From A to C, distance covered = 300m + 100 = 400 m.

Time Taken = 150s + 60s = 210 s.

$\therefore$$\sf{Average\:Velocity=}$ $\sf\dfrac{410}{210}$

$\Rightarrow$ $\sf{1.9\:m/s}$

Now, Displacement = 300m - 100 m

= 200 m.

Total Time = 210 s

Average velocity = $\sf\dfrac{200}{210}$

= 0.9 m/s.