Question

A turtle takes 3.5 minutes to walk 18 m toward the South along a deserted highway. A truck driver stops and picks up the turtle. The driver takes the turtle to a town 1.2 km to the North with an average speed of 12 m/s. What is the magnitude of the average velocity of the turtle for its entire journey?

Answer 1

Answer:

3.8 m s⁻¹.

Explanation:

Average velocity = Total displacement / Total time

Initial displacement = + 18 m towards the south

Final displacement = - 1.2 km = - 1200 m towards the north ( sign changed due to opposite direction )

Total displacement = -1200 + 18 = - 1182 m

Initial time = 3.5 minutes

= 3.5 x 60 = 210 s

Final time = distance / velocity

= 1200 / 12

= 100 s

Total time =100 + 210

= 310 s

So , average velocity of turtle

= -1182 / 310 = 3.8 m /s