A grass trimmer for landscaping has a rotating head which consists of a spool of nylon line, with a strand of line that extends out from the edge. The spool has an inner diameter of 3.00 cm and an outer diameter of 18.0 cm, and a mass of 100 g. The strand has a length of 16.0 cm. The nylon line has a linear density of 10.0 g/m. 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 0.175 s. What average power (in W) is delivered to the head by the trimmer motor while it is accelerating? (Round your answer to at least one decimal place.) (b) When the trimmer is cutting grass, it spins at 2,100 rev/min and the grass exert an average tangential force of 6.15 N on the outer end of the line, which is still at a radial distance of 16.0 cm from the outer edge of the spool. What is the power (in W) delivered to the head under load?

A grass trimmer for landscaping has a rotating head which consists of a spool of nylon line, with a strand of line that extends out from the edge. The spool has an inner diameter of 3.00 cm and an outer diameter of 18.0 cm, and a mass of 100 g. The strand has a length of 16.0 cm. The nylon line has a linear density of 10.0 g/m. 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 0.175 s. What average power (in W) is delivered to the head by the trimmer motor while it is accelerating? (Round your answer to at least one decimal place.) (b) When the trimmer is cutting grass, it spins at 2,100 rev/min and the grass exert an average tangential force of 6.15 N on the outer end of the line, which is still at a radial distance of 16.0 cm from the outer edge of the spool. What is the power (in W) delivered to the head under load?

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Description: A grass trimmer for landscaping has a rotating head which consists of a spool of nylon line, with a strand of line that extends out from the edge. The spool hasan inner diameter of 3.00 cm and an outer diameter of 18.0 cm, and a mass of 100 g. The s

College Physics

1st Edition

ISBN:9781938168000

Author:Paul Peter Urone, Roger Hinrichs

Publisher:Paul Peter Urone, Roger Hinrichs

Chapter11: Fluid Statics

Section: Chapter Questions

Problem 75PE: Pressure in the spinal fluid is measured as shown in Figure 11.43. If the pressure in the spinal...

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