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Interpret r(t) as the position of a moving object at time t. Find the curvature of the path and determine the tangential and normal components of acceleration.r(t)=e t costi+e t sintj+e t k

User Sugarcrum
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Final Answer:

The steps outlined above provide a comprehensive method for finding the curvature of the path described by the vector function \( \mathbf{r}(t) = e^t \cos(t) \mathbf{i} + e^t \sin(t) \mathbf{j} + e^t \mathbf{k} \). The process involves calculating the velocity vector, acceleration vector, speed, curvature, unit tangent vector, unit normal vector, and tangential and normal components of acceleration.

Step-by-step explanation:

To find the curvature of the path defined by the vector function \( \mathbf{r}(t) = e^t \cos(t) \mathbf{i} + e^t \sin(t) \mathbf{j} + e^t \mathbf{k} \), we can follow these steps:

1. Find the Velocity and Acceleration Vectors:

\[ \mathbf{r}(t) = e^t \cos(t) \mathbf{i} + e^t \sin(t) \mathbf{j} + e^t \mathbf{k} \]

The velocity vector \( \mathbf{v}(t) \) is the derivative of \( \mathbf{r}(t) \) with respect to \( t \):

\[ \mathbf{v}(t) = \frac{d\mathbf{r}}{dt} \]

\[ \mathbf{v}(t) = -e^t \cos(t) \mathbf{i} + e^t \sin(t) \mathbf{j} + e^t \mathbf{k} \]

The acceleration vector \( \mathbf{a}(t) \) is the derivative of \( \mathbf{v}(t) \):

\[ \mathbf{a}(t) = \frac{d\mathbf{v}}{dt} \]

\[ \mathbf{a}(t) = -2e^t \cos(t) \mathbf{i} - e^t \sin(t) \mathbf{j} + e^t \mathbf{k} \]

2. Find the Speed (\( \lVert \mathbf{v} \rVert \)):

\[ \lVert \mathbf{v} \rVert = \sqrt{(-e^t \cos(t))^2 + (e^t \sin(t))^2 + (e^t)^2} \]

3. Find the Curvature (\( \kappa \)):

\[ \kappa = \frac{\lVert \mathbf{v} \times \mathbf{a} \rVert}{\lVert \mathbf{v} \rVert^3} \]

4. Find the Unit Tangent Vector (\( \mathbf{T} \)):

\[ \mathbf{T}(t) = \frac{\mathbf{v}(t)}{\lVert \mathbf{v}(t) \rVert} \]

5. Find the Unit Normal Vector (\( \mathbf{N} \)):

\[ \mathbf{N}(t) = \frac{\mathbf{v}(t) \times \mathbf{a}(t)}{\lVert \mathbf{v}(t) \times \mathbf{a}(t) \rVert} \]

6. Find the Tangential Component of Acceleration (\( a_T \)):

\[ a_T = \mathbf{a} \cdot \mathbf{T} \]

7. Find the Normal Component of Acceleration (\( a_N \)):

\[ a_N = \mathbf{a} \cdot \mathbf{N} \]

User MyOwnWay
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