An ice skater has a moment of inertia of 2.5 kg.m2 when her arms are extended and a moment of inertia of 1.2 kg.m2 when her arms are pulled in close to her body. If she goes into a spin with her arms extended and has an initial angular velocity of 2.3 rad/s, what is her angular velocity when she pulls her arms in close to her body? Answer in units of rad/

Respuesta :

Answer:

[tex]\omega=4.7916\ rad.s^{-1}[/tex]

Explanation:

Given:

  • moment of inertia of the skater with extended arms, [tex]I'=2.5\ kg.m^2[/tex]
  • moment of inertia of the the skater with pulled-in arms, [tex]I=1.2\ kg.m^2[/tex]
  • angular velocity of the skater with extended arms, [tex]\omega'=2.3\ rad.s^{-1}[/tex]

Using the law of conservation of angular momentum:

[tex]I'.\omega'=I.\omega[/tex]

[tex]2.5\times 2.3=1.2\times \omega[/tex]

[tex]\omega=4.7916\ rad.s^{-1}[/tex]