The figure shows an approximate plot of stress versus strain for a spider-web thread, out to the point of breaking at a strain of 2.20. The vertical axis scale is set by a = 0.190 GN/m²,b = 0.300 GN/m?, and c = 0.720 GN/m². Assume that the thread has an initial length of 0.720 cm, an initial cross-sectional area of 4.00 × 10-12 m², and (during stretching) a constant volume. The strain on the thread is the ratio of the change in the thread's length to that initial length, and the stress on the thread is the ratio of the collision force to that initial cross-sectional area. Assume also that when the single thread snares a flying insect, the insect's kinetic energy is transferred to the stretching of the thread. (a) How much kinetic energy would put the thread on the verge of breaking? What is the kinetic energy of (b) a fruit fly of mass 7.50 mg and speed 2.00 m/s and (c) a bumble bee of mass 0.370 g and speed 0.800 m/s? Would (d) the fruit fly and (e) the bumble bee break the thread? 1.00 1.25 2.20 Strain Stress (GN/m²)

The figure shows an approximate plot of stress versus strain for a spider-web thread, out to the point of breaking at a strain of 2.20. The vertical axis scale is set by a = 0.190 GN/m²,b = 0.300 GN/m?, and c = 0.720 GN/m². Assume that the thread has an initial length of 0.720 cm, an initial cross-sectional area of 4.00 × 10-12 m², and (during stretching) a constant volume. The strain on the thread is the ratio of the change in the thread's length to that initial length, and the stress on the thread is the ratio of the collision force to that initial cross-sectional area. Assume also that when the single thread snares a flying insect, the insect's kinetic energy is transferred to the stretching of the thread. (a) How much kinetic energy would put the thread on the verge of breaking? What is the kinetic energy of (b) a fruit fly of mass 7.50 mg and speed 2.00 m/s and (c) a bumble bee of mass 0.370 g and speed 0.800 m/s? Would (d) the fruit fly and (e) the bumble bee break the thread? 1.00 1.25 2.20 Strain Stress (GN/m²)

College Physics

11th Edition

ISBN:9781305952300

Author:Raymond A. Serway, Chris Vuille

Publisher:Raymond A. Serway, Chris Vuille

Chapter9: Fluids And Solids

Section: Chapter Questions

Problem 73P: A high-speed lifting mechanism supports an 800.-kg object with a steel cable that is 25.0 m long and...

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