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 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. 16.0 cm -3.00 cm 18.0 cm (a) When switched on, the trimmer speeds up from 0 to 2 550 rev/min in 0.240 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 2 025 rev/min and the grass exerts an average tangential force of 8.30 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

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 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. 16.0 cm -3.00 cm 18.0 cm (a) When switched on, the trimmer speeds up from 0 to 2 550 rev/min in 0.240 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 2 025 rev/min and the grass exerts an average tangential force of 8.30 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