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The components of a position vector of a particle moving in the plane are
(t^3, 2sin(t))

What is the distance traveled by the particle from t = 1 to t = π?

1 Answer

1 vote

Answer:

30.113

Explanation:

r(t) = (t³, 2 sin t)

The distance traveled is the length of the path (arc length):

L = ∫ₐᵇ √((dx/dt)² + (dy/dt)²) dt

L = ∫₁ᵖⁱ √((3t²)² + (2 cos t)²) dt

L = ∫₁ᵖⁱ √(9t⁴ + 4 cos²t) dt

Using a calculator:

L ≈ 30.113

Notice that distance is not the same as displacement. If we wanted to find the displacement:

r(π) = (π³, 0)

r(1) = (1, 2 sin 1)

Δr = √((π³ − 1)² + (0 − 2 sin 1)²)

Δr ≈ 30.053

User MR Mido
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