In a needle biopsy, a narrow strip of tissue is extracted from a patient with a hollow needle. Rather than being pushed by hand, to ensure a clean cut the needle can be fired into the patient's body by a spring. Assume the needle has mass 5.60 g, the light spring has force constant 395 N/m, and the spring is originally compressed 8.10 cm to project the needle horizontally without friction. (The spring is fully uncompressed before the needle contacts the skin.) The tip of the needle then moves through 2.40 cm of skin and soft tissue, which exerts a resistive force of 7.10 N on it. Next, the needle cuts 3.50 cm into an organ, which exerts a backward force of 9.40 N on it. (a) Find the maximum speed of the needle. m/s (b) Find the speed at which a flange on the back end of the needle runs into a stop, set to limit the penetration to 5.90 cm. m/s

In a needle biopsy, a narrow strip of tissue is extracted from a patient with a hollow needle. Rather than being pushed by hand, to ensure a clean cut the needle can be fired into the patient's body by a spring. Assume the needle has mass 5.60 g, the light spring has force constant 395 N/m, and the spring is originally compressed 8.10 cm to project the needle horizontally without friction. (The spring is fully uncompressed before the needle contacts the skin.) The tip of the needle then moves through 2.40 cm of skin and soft tissue, which exerts a resistive force of 7.10 N on it. Next, the needle cuts 3.50 cm into an organ, which exerts a backward force of 9.40 N on it. (a) Find the maximum speed of the needle. m/s (b) Find the speed at which a flange on the back end of the needle runs into a stop, set to limit the penetration to 5.90 cm. m/s

Principles of Physics: A Calculus-Based Text

5th Edition

ISBN:9781133104261

Author:Raymond A. Serway, John W. Jewett

Publisher:Raymond A. Serway, John W. Jewett

Chapter7: Conservation Of Energy

Section: Chapter Questions

Problem 83P

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