You're looking at a worksheet titled
“Interpreting Motion Graphs”, specifically
Section A: Displacement.
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## 🎯 GOAL:
Calculate the
displacement (Δx) of a little dude in each scenario using the formula:
>
Δx = x_f – x_i
Where:
-
x_i = initial position (at time t = 0 s)
-
x_f = final position (at time t = 4 s — since each image shows motion over 4 seconds, as indicated by the x-axis)
Displacement is a
vector — it has direction! So we must include
sign (+ for east, – for west, based on the problem’s convention).
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Let’s go through each part:
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✔ (a) Little dude walks to the east.
Image Description:
At t=0, he starts at
x = 0 m.
At t=4 s, he ends at
x = +4 m (east).
> Δx = x_f – x_i = 4 m – 0 m =
+4 m
✔ Answer: +4 meters (or 4 m east)
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✔ (b) Little dude walks to the west.
Image Description:
At t=0, he starts at
x = 0 m.
At t=4 s, he ends at
x = –4 m (west).
> Δx = x_f – x_i = –4 m – 0 m =
–4 m
✔ Answer: –4 meters (or 4 m west)
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✔ (c) Little dude walks to the east, then west.
Image Description:
At t=0, he starts at
x = 0 m.
He walks east to
x = +2 m at t=2 s, then turns around and walks west to
x = –2 m at t=4 s.
> Δx = x_f – x_i = –2 m – 0 m =
–2 m
⚠️ Note: Even though he walked a total *distance* of 4 m (2 m east + 2 m west), displacement only cares about
start and end positions.
✔ Answer: –2 meters (or 2 m west)
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✔ (d) Little dude is sitting reading a book.
Image Description:
He doesn’t move at all — stays at
x = 0 m from t=0 to t=4 s.
> Δx = x_f – x_i = 0 m – 0 m =
0 m
✔ Answer: 0 meters (no displacement — he didn’t change position)
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## 📝 Final Answers:
(a) +4 m
(b) –4 m
(c) –2 m
(d) 0 m
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## 💡 KEY CONCEPT REMINDER:
>
Displacement ≠ Distance
> - Displacement is
change in position (vector — includes direction).
> - Distance is
total path length traveled (scalar — no direction).
> In (c), distance = 4 m, but displacement = –2 m.
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Let me know if you want help with Section B (Velocity/Speed) next! 😊
Parent Tip: Review the logic above to help your child master the concept of interpreting motion graphs worksheet.
