Number 8 8. A 50 kg ice skater spins about a vertical axis through her body with her arms horizontally outstretched,making 2.5 turns each second. The distance from one hand to the other is 1.50 m. Biometricmeasurements indicate that each hand typically makes up about 1.25 % of body weight.What horizontal force must her wrist exert on her hand?Express the force in part (a) as a multiple of the weight of her hand.11. A small button placed on a horizontal, rotating platform with diameter 0.320 m will revolve with theplatform when it is brought up to a rotational speed of 37.0 rev/min, provided the button is no more than0.140 m from the axis.What is the coefficient of static friction between the button and the platform? coHow far from the axis can the button be placed, without slipping, if the platform rotates at 60.0 rev/min?oge tw o leinosnod13. A 5.0-m-diameter merry-go-round is turning with a 4.2 s period. What is the speed of a child on the rim?14. The blade on a table saw spins at 3800 rpm . Its diameter is 25.0 cm.What is the speed of a tooth on the edge of the blade in m/s?What is the speed of a tooth on the edge of the blade in mph?15. An old-fashioned LP record rotates at 33½ rpm.What is its frequency in rev/s?What is its period, in seconds?16. A typical hard disk in a computer spins at 10000 rpm.What is the frequency, in rev/s?What is the period, in seconds?Sns beutbloow17. A CD-ROM drive in a computer spins the 12-cm-diameter disks at 7300 rpm.

Given, mass of skater = 50 kg Making 2.5 turns each second means angular velocity , ω = 2.5×2π…

Answered: 8. A 50 kg ice skater sp making 2.5…

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Physics

8. A 50 kg ice skater sp making 2.5 turns eac measurements indica What horizontal for

College Physics

1st Edition

ISBN:9781938168000

Author:Paul Peter Urone, Roger Hinrichs

Publisher:Paul Peter Urone, Roger Hinrichs

Chapter9: Statics And Torque

Section: Chapter Questions

Problem 37PE: (a) What force should the woman in Figure 9.45 exert on the floor with each hand to do a push-up?...

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