More Motion Terms
Displacement
Displacement - distance & direction from start to finish
Fill In The Blanks NotesDisplacement
When studying motion, physicists find it more useful to measure the displacement of an object rather than the distance. Displacement refers to the object's change in position from its starting point to its finishing point, taking both distance and direction into account.
How can you travel a distance of 10 meters but have a zero displacement?
Science Requires Careful Observations
Why does this boat float?
Ship floating on nothing! :: Physikshow Uni Bonn
School blocks YouTube? Use the file below | Onsite
Sulfur hexafluoride is more dense than the surrounding air
When physicists study motion they study displacement, not distance.
Video Instruction
showmethephysics.com
Enduring Understanding
1. Displacement is an object's distance and direction traveled from start to finish. (What happens in between doesn't matter.)
2. + is up, right, east and forward.
1) Examples
Displacement? 1 m up
Displacement? 3 m Right
2) Displacement Always Has ...
Magnitude
(a number)
...and Direction
a) Examples: 5 m East • 7 m upward • +17 m
b) Positive and negative signs also show direction.
+ — usually up, right, north, east, forward
− — usually down, left, south, west, backwards
c) Symbol for displacement: d
Summary Review
[ Flash ]
At what point is the displacement: 1) greatest? 2) zero? 3) equal to distance? 4) What is the displacement at C?
Check Your Understanding
5 quick questions — pick an answer to see if you’re right.
1. What is displacement?
2. A student walks 5 m east and then 5 m back west. What are the distance and displacement?
3. A hiker walks 4 m north and then 3 m east. What is the magnitude of the hiker's displacement?
4. Using the usual sign convention, a displacement of −8 m most likely means...
5. Which of these is a complete displacement?
Hospital Delivery Robot
Hospitals use self-driving robots to deliver medicine. One robot leaves the pharmacy, travels 30. meters east down a hallway, turns, and travels 40. meters north to a nurses’ station. The trip takes 100. seconds.
Diagram 1: Robot’s Path (top view)
(Not drawn to scale)
What are the total distance traveled and the magnitude of the displacement of the robot?
▶ Want a challenge? Open 6 more Regents-style questions (harder · mixed formats)
Challenge score: 0 / 6
C1. A hospital manager makes the following claim.
Place a check mark in either the Support or Refute box. Justify your response.
C2. After a short stop, the robot returns to the pharmacy by retracing its path. For the round trip, what are the distance and displacement?
C3. The magnitude of the robot’s displacement is 50. m. Substitute numerical values into a mathematical representation that can be used to determine the magnitude of the robot’s average velocity for the trip. Then calculate it.
C4. Assume the robot moves at a constant speed with no stops for the entire 100.-second trip. While it travels the 40.-meter hallway, choose the direction of its velocity and determine its magnitude. (North is up, east is to the right, as in Diagram 1.)
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C5. What is the direction of the robot’s displacement from the pharmacy to the nurses’ station?
C6. The hospital wants deliveries along the same hallway path to take only 50. s. Determine the average speed the robot would need, and identify one drawback of this design change.
