The vertical motion of mass A is defined by the relation x 5 10 sin 2t 1 15 cos 2t 1 100, where x and t are expressed in millimeters and seconds, respectively. Determine (a) the position, velocity, and acceleration of A when t 5 1 s, (b) the maximum velocity and acceleration of A.

Respuesta :

Explanation:

Given that,

The vertical motion of mass A is defined by the relation as :

[tex]x=10\ sin2t+15\ cos2t+100[/tex]

At t = 1 s

[tex]x=10\ sin2+15\ cos2+100[/tex]

x = 115.33 mm

(a) We know that,

Velocity, [tex]v=\dfrac{dx}{dt}[/tex]

[tex]v=\dfrac{d(10\ sin2t+15\ cos2t+100)}{dt}[/tex]

[tex]v=20\ cos2t-30\ sin2t[/tex]

At t = 1 s

[tex]v=20\ cos2-30\ sin2[/tex]

v = 18.94 mm/s

We know that,

Acceleration, [tex]a=\dfrac{dv}{dt}[/tex]

[tex]a=\dfrac{d(20\ cos2-30\ sin2)}{dt}[/tex]

[tex]a=-40\ cos2t-60\ cos2t[/tex]

At t = 1 s

[tex]v=-40\ cos2-60\ cos2[/tex]

[tex]a=-99.93\ mm/s^2[/tex]

(b) For maximum velocity, [tex]\dfrac{dv}{dt}=a=0[/tex]

[tex]-40\ cos2t-60\ cos2t=0[/tex]

t = 45 seconds

For maximum acceleration, [tex]\dfrac{da}{dt}=0[/tex]

[tex]80\ sin2t+120\ cos2t=0[/tex]

t = 61.8 seconds

Hence, this is the required solution.

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