103k views
2 votes
Suppose you walk 18.0 m straight west and then 25.0 m straight north. How far are you from your starting point? What is your displacement vector? What is the direction of your displacement? Assume the +x-axis is to the east.

a) 30.0 m; 30.0 m, 53.1° north of west
b) 7.0 m; 7.0 m, 53.1° north of west
c) 7.0 m; 30.0 m, 36.9° north of west
d) 30.0 m; 7.0 m, 36.9° north of west

User Rkersh
by
8.2k points

1 Answer

4 votes

Final answer:

The total distance from the starting point is approximately 30.8 m, and the direction of the displacement vector is 54.0° north of west.

Step-by-step explanation:

To determine how far you are from the starting point after walking 18.0 m straight west and then 25.0 m straight north, you can use the Pythagorean theorem. In this context, the displacement vectors are perpendicular to each other, therefore:

  • The displacement to the west is represented as -18.0 m along the x-axis (since west is the negative direction on the x-axis).
  • The displacement to the north is represented as 25.0 m along the y-axis.

To find the total displacement vector, we calculate the magnitude:

√((-18.0 m)² + (25.0 m)²) = √(324 + 625) = √(949) ≈ 30.8 m

To find the direction of the displacement vector, we use the tangent of the angle, θ:

tan(θ) = opposite/adjacent = 25.0 m / 18.0 m

θ = arctan(25.0 m / 18.0 m) ≈ 54.0°

Since we have moved west and north, the direction of the displacement is 54.0° north of west. The correct answer from the choices is closest to option (a): approximately 30.8 m; 30.8 m, 54.0° north of west.

User Tisa
by
8.4k points