outside diameter 18.0 cm as shown in the figure below. The cord has a linear density of 10.0 g/m. A single strand of the cord extends 16.0 cm from the outer edge of the spool. The head of a grass string trimmer has 100 g of cord wound in a light, cylindrical spool with inside diameter 3.00 cm and -16.0 cm +3.00 cm 18.0 cm (a) When switched on, the trimmer speeds up from 0 to 2 250 rev/min in 0.230 s. What average power is delivered to the head by the trimmer motor while it is accelerating? W (b) When the trimmer is cutting grass, it spins at 1 940 rev/min and the grass exerts an average tangential force of 8.85 N on the outer end of the cord, which is still at a radial distance of 16.0 cm from the outer edge of the spool. What is the power delivered to the head under load? W

outside diameter 18.0 cm as shown in the figure below. The cord has a linear density of 10.0 g/m. A single strand of the cord extends 16.0 cm from the outer edge of the spool. The head of a grass string trimmer has 100 g of cord wound in a light, cylindrical spool with inside diameter 3.00 cm and -16.0 cm +3.00 cm 18.0 cm (a) When switched on, the trimmer speeds up from 0 to 2 250 rev/min in 0.230 s. What average power is delivered to the head by the trimmer motor while it is accelerating? W (b) When the trimmer is cutting grass, it spins at 1 940 rev/min and the grass exerts an average tangential force of 8.85 N on the outer end of the cord, which is still at a radial distance of 16.0 cm from the outer edge of the spool. What is the power delivered to the head under load? W

Physics for Scientists and Engineers: Foundations and Connections

1st Edition

ISBN:9781133939146

Author:Katz, Debora M.

Publisher:Katz, Debora M.

Chapter15: Fluids

Section: Chapter Questions

Problem 43PQ

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Similar questions

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