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8.4: Motion in Space

  • Page ID
    144339
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    1. The position of a particle at time \(t\) is given by the function \(\mathbf{r}(t) = (3t^2 - 2, 2t - \sin t)\). Find the velocity, acceleration, and speed of this particle in terms of \(t\).
       
    2. The position of a particle at time \(t\) is given by the function \(\mathbf{r}(t) = 2\sin t\,\mathbf{i} + 2\cos t\,\mathbf{j} + t^2\,\mathbf{k}\). Find the velocity, acceleration, and speed of the particle in terms of \(t\).
       
    3. The position of a particle at time \(t\) is given by the function \(\mathbf{r}(t) = (e^{-t}, t^2, \tan t)\). Find the velocity, acceleration, and speed of the particle in terms of \(t\).
       
    4. A projectile is launched into the air from ground level with an initial speed of 50 m/sec at an angle of 60° with the horizontal. Construct a vector-valued function that models the position of the projectile \(t\) seconds after it is launched.
       
    5. A ball is thrown horizontally off the edge of a 540 m tall skyscraper with an initial speed of 40 m/sec. Construct a vector-valued function that models the position of the projectile \(t\) seconds after it is launched.
       
    6. A projectile is launched 1.5 m above the surface of Mars with an initial speed of 100 m/sec at an angle of 45° with the horizontal. Given that the acceleration due to gravity on Mars is \(g = -3.71 \text{m}/\text{sec}^2\), construct a vector-valued function that models the position of the projectile \(t\) seconds after it is launched.
       
    7. The position of a particle at time \(t\) is given by the function \(\mathbf{r}(t) = \cos t\,\mathbf{i} + \sin t\,\mathbf{j} + t\,\mathbf{k}\). Find the tangential and normal components of acceleration when \(t = 0\).
       
    8. The position of a particle at time \(t\) is given by the function \(\mathbf{r}(t) = \left(2t, t^2, \dfrac{t^3}{3}\right)\). Find the tangential and normal components of acceleration when \(t = 1\).
       
    9. The position of a particle at time \(t\) is given by the function \(\mathbf{r}(t) = 2t^3\,\mathbf{i} + 3t^2\,\mathbf{j} + 6t\,\mathbf{k}\). Find the tangential and normal components of acceleration at \(t = -1\).

    8.4: Motion in Space is shared under a not declared license and was authored, remixed, and/or curated by LibreTexts.

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