DNA molecules are typically folded tightly. Stretching a strand of DNA means straightening it, and the molecules resist this straightening. Investigators can attach beads to the ends of a strand of DNA and, using "optical tweezers," measure the force required to produce a certain extension. Data for the stretch of a 3500 base pair strand of DNA approximately follow the line in the graph shown below. What is the spring constant for this strand of DNA? 1.0 pN=1.0 x 10-12 N and 1.0 nm = 1.0 x 10-9 m. Restoring force (pN) 0.06- 0.04- 0.02- 0 4.0 N/m 3.0 N/m 0 O 2.5 N/m O 2.5 x 10-7 N/m 50 100 150 200 Extension (nm)

DNA molecules are typically folded tightly. Stretching a strand of DNA means straightening it, and the molecules resist this straightening. Investigators can attach beads to the ends of a strand of DNA and, using "optical tweezers," measure the force required to produce a certain extension. Data for the stretch of a 3500 base pair strand of DNA approximately follow the line in the graph shown below. What is the spring constant for this strand of DNA? 1.0 pN=1.0 x 10-12 N and 1.0 nm = 1.0 x 10-9 m. Restoring force (pN) 0.06- 0.04- 0.02- 0 4.0 N/m 3.0 N/m 0 O 2.5 N/m O 2.5 x 10-7 N/m 50 100 150 200 Extension (nm)

University Physics Volume 1

18th Edition

ISBN:9781938168277

Author:William Moebs, Samuel J. Ling, Jeff Sanny

Publisher:William Moebs, Samuel J. Ling, Jeff Sanny

Chapter7: Work And Kinetic Energy

Section: Chapter Questions

Problem 39P: A bungee cord is essentially a very long rubber band that can stretch up to four times its...

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