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A 245-kg merry-go-round in the shape of a uniform, solid, horizontal disk of radius 1.50 m is set in motion by wrapping a rope about the rim of the disk and pulling on the rope. What constant force would have to be exerted on the rope to bring the merry-go-round from rest to an angular speed of 0.600 rev/s in 2.00 s? (State the magnitu

Respuesta :

Answer:

F = 345.45 N

Explanation:

Angular acceleration of the disc is given as rate of change in angular speed

it is given by formula

[tex]\alpha = \frac{d\omega}{dt}[/tex]

[tex]\alpha = \frac{2\pi(0.600)}{2}[/tex]

[tex]\alpha = 1.88 rad/s^2[/tex]

now we know that moment of inertia of the solid uniform disc is given as

[tex]I = \frac{1}{2}mR^2[/tex]

[tex]I = \frac{1}{2}245(1.50)^2[/tex]

[tex]I = 275.625 kg m^2[/tex]

now we have an equation for torque as

[tex]\Tau = I\alpha[/tex]

[tex]r F = 275.625(1.88)[/tex]

[tex]F = \frac{275.625(1.88)}{1.50}[/tex]

[tex]F = 345.45 N[/tex]