You walk from your bedroom, 25m to the mailbox, and then walk 25m back to your bedroom. What is your total distance? What is your displacement?

Distance is 50m

Displacement is 0m

Explanation:

Distance is based on the amount of length you covered, regardless of where you end.

Displacement only considered where you started and where you ended, which is at the same spot in this case. Therefore, no displacement.

acceleration = (change in speed) / (time for the change)

change in speed = (20-120)= -100 m/s.

1.5 min = 90 sec

acceleration = -100/90 = -1.11 m/s^2.

we don't care about the 150kg or the 2,500 meters. they don't make any difference.

read more on -