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Consider the following position functions. a. Find the velocity and speed of the object. b. Find the acceleration of the object. $$\mathbf{r}(t)=\left\langle 1, t^{2}, e^{-t}\right\rangle, \text { for } t \geq 0$$

Short Answer

Expert verified
Answer: The velocity function is $$\mathbf{v}(t) = \left\langle 0, 2t, -e^{-t} \right\rangle$$, the speed is $$\text{Speed} = \| \mathbf{v}(t) \| = \sqrt{4t^2 + e^{-2t}\ }$$, and the acceleration function is $$\mathbf{a}(t) = \left\langle 0, 2, e^{-t} \right\rangle$$.

Step by step solution

01

Calculate the Velocity function

To calculate the velocity function, we need to find the derivative of the given position function with respect to time. So, the velocity function will be the first derivative of the position function $$ \mathbf{v}(t) = \frac{d\mathbf{r}(t)}{dt} = \left\langle \frac{d}{dt}(1), \frac{d}{dt}(t^2), \frac{d}{dt}(e^{-t})\right\rangle $$ Now, we differentiate each component with respect to t: $$ \mathbf{v}(t) = \left\langle 0, 2t, -e^{-t} \right\rangle $$
02

Calculate the Speed of the object

The speed is the magnitude of the velocity vector. To find the magnitude, we take the square root of the sum of squares of the individual components of the velocity vector: $$ \text{Speed} = \| \mathbf{v}(t) \| = \sqrt{(0)^2 + (2t)^2 + (-e^{-t})^2} = \sqrt{4t^2 + e^{-2t}\ } $$
03

Calculate the Acceleration function

To find the acceleration function, we need to take the derivative of the velocity function with respect to time. The acceleration function will be the first derivative of the velocity function: $$ \mathbf{a}(t) = \frac{d\mathbf{v}(t)}{dt} = \left\langle \frac{d}{dt}(0), \frac{d}{dt}(2t), \frac{d}{dt}(-e^{-t})\right\rangle $$ Now, we differentiate each component with respect to t: $$ \mathbf{a}(t) = \left\langle 0, 2, e^{-t} \right\rangle $$ The velocity, speed, and acceleration functions have been found as: 1. Velocity function: $$\mathbf{v}(t) = \left\langle 0, 2t, -e^{-t} \right\rangle$$ 2. Speed: $$\text{Speed} = \| \mathbf{v}(t) \| = \sqrt{4t^2 + e^{-2t}\ } $$ 3. Acceleration function: $$\mathbf{a}(t) = \left\langle 0, 2, e^{-t} \right\rangle $$

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Most popular questions from this chapter

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