Question

Jojo and Roro begin side-by-side at one end of the playground. At the same moment, they begin to move toward the other end of the playground, Jojo at a constant velocity of 3.0 m/s, Roro at a constant velocity of 2.0 m/s. Sometime during her trip, Roro stops to rest for 2.0 s, but then starts again at her original constant speed. When Jojo reaches the end of the playground, she is 10 m ahead of Roro.

(a) For how much time did Roro move?
(b) How far did Roro move? (Set it up, good notation, equations in symbols first, etc.)

Answer 1

Roro's total travel time = 6 seconds out of which he rested for 2 seconds

Distance covered by Roro = 8 meters

Step-by-step explanation:

Given that :

Jojo:

Constant velocity, v = 3m/s

Travel time = h

Roro:

Constant velocity, v = 2m/s

Roro rest for 2 seconds

Travel time = h - 2

Recall:

Distance = speed * time

Distance covered by Jojo:

3 * h = 3h

At this distance ;

Roro's distance = 3h - 10

Using formula :

Roro's distance = 2 * (h - 2)

Hence,

2(h - 2) = 3h - 10

2h - 4 = 3h - 10

2h - 3h = - 10 + 4

-h = - 6

h = 6

Hence, Roro moved for :

h - 2 = 6 - 2 = 4seconds

Distance moved by Roro:

2(h - 2) = 2(6 - 2) = 2(4) = 8 meters