The position function of a particle is given by r(t) = t2, 2t, t2 − 16t . When is the speed a minimum? Step 1 To find when the speed is a minimum, we need to find the speed as a function of t, then find its derivative and see when it is 0. We begin by finding the velocity vector. Since r(t) = t2, 2t, t2 − 16t , we have v(t) = r'(t) = .

Respuesta :

Answer:

The speed is minimum at t = 2.

Step-by-step explanation:

The position of a particle is given by [tex]r(t) = t^{2}, 2t, t^{2} - 16t.[/tex]

Differentiating the above with respect to t, we get, velocity v(t) = [tex][2t, 2, 2t - 16][/tex].

Hence, the speed of the particle at t is [tex]\sqrt{(2t)^2 + (2)^2 + (2t - 16)^2 } = \sqrt{4t^2 + 4 + 4t^2 - 64t + 256} = \sqrt{16t^2 -64t + 260}[/tex].

The speed will be minimum, if

[tex]\frac{d \sqrt{16t^2 - 64t + 260} }{dt} = 0\\\frac{32t - 64}{2\sqrt{16t^2 - 64t + 260}} = 0\\\frac{16t - 32}{\sqrt{16t^2 - 64t + 260}} = 0\\t = \frac{32}{16} = 2[/tex].

The speed will be minimum at t = 2.

At t=2, the speed is 14.

The speed is minimum at  t = 4 seconds.

The position function of a particle is given by

                      [tex]r(t) = t^{2},2t,t^{2}-16t[/tex]

The velocity is given as,

        [tex]v=\frac{dr(t)}{dt} =2t,2,2t-16[/tex]

Speed is computed as,

  [tex]Speed=\sqrt{(2t)^{2}+2^{2}+(2t-16)^{2} }\\ \\v=\sqrt{8t^{2}-64t+260 }[/tex]

Differentiate above expression and equate to zero.

 [tex]\frac{dv}{dt}=\frac{16t-64}{2\sqrt{8t^{2} -64t+260} } =0\\\\16t=64\\\\t=64/16=4[/tex]

Thus, speed is minimum at  t = 4 seconds.

Learn more:

https://brainly.com/question/954654