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A gyroscope flywheel of radius 3.21 cm is accelerated from rest at 13.2 rad/s2 until its angular speed is 2450 rev/min.
(a) What is the tangential acceleration of a point on the rim of the flywheel during this spin-up process?
(b) What is the radial acceleration of this point when the flywheel is spinning at full speed?
(c) Through what distance does a point on the rim move during the spin-up?

Respuesta :

Answer:

Part a)

[tex]a_t = 0.423 m/s^2[/tex]

Part b)

[tex]a_c = 2113 m/s^2[/tex]

Part c)

[tex]d = 80 m[/tex]

Explanation:

Part a)

as we know that angular acceleration of the wheel is given as

[tex]\alpha = 13.2 rad/s^2[/tex]

now the radius of the wheel is given as

R = 3.21 cm

so the tangential acceleration is given as

[tex]a_t = R\alpha[/tex]

[tex]a_t = (0.0321)(13.2)[/tex]

[tex]a_t = 0.423 m/s^2[/tex]

Part b)

frequency of the wheel at maximum speed is given as

[tex]f = 2450 rev/min[/tex]

[tex]f = \frac{2450}{60} = 40.8 rev/s[/tex]

now we know that

[tex]\omega = 2\pi f = 2\pi(40.8) = 256.56 rad/s[/tex]

now radial acceleration is given as

[tex]a_c = \omega^2 r[/tex]

[tex]a_c = (256.56)^2(0.0321) = 2113 m/s^2[/tex]

Part c)

total angular displacement of the point on rim is given as

[tex]\Delta \theta = \omega_0 t + \frac{1}{2}\alpha t^2[/tex]

here we know that

[tex]\omega = \omega_0 + \alpha t[/tex]

[tex]256.56 = 0 + 13.2 t[/tex]

[tex]t = 19.4 s[/tex]

now angular displacement will be

[tex]\Delta \theta = 0 + \frac{1}{2}(13.2)(19.4)^2[/tex]

[tex]\Delta \theta = 2493.3 rad[/tex]

now the distance moved by the point on the rim is given as

[tex]d = R\theta[/tex]

[tex]d = (0.0321)(2493.3)[/tex]

[tex]d = 80 m[/tex]

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