The elastic energy stored in your tendons can contribute up to 35% of your energy needs when running. Sports scientists find that (on average) the knee extensor tendons in sprinters stretch 45 mm while those of nonathletes stretch only 32 mm. The spring constant of the tendon is the same for both groups, 33 N/mm. What is the difference in maximum stored energy between the sprinters and the nonathletes? Express your answer with the appropriate units. ► View Available Hint(s) AU = Submit μÀ Value Units ?

The elastic energy stored in your tendons can contribute up to 35% of your energy needs when running. Sports scientists find that (on average) the knee extensor tendons in sprinters stretch 45 mm while those of nonathletes stretch only 32 mm. The spring constant of the tendon is the same for both groups, 33 N/mm. What is the difference in maximum stored energy between the sprinters and the nonathletes? Express your answer with the appropriate units. ► View Available Hint(s) AU = Submit μÀ Value Units ?

College Physics

11th Edition

ISBN:9781305952300

Author:Raymond A. Serway, Chris Vuille

Publisher:Raymond A. Serway, Chris Vuille

Chapter1: Units, Trigonometry. And Vectors

Section: Chapter Questions

Problem 1CQ: Estimate the order of magnitude of the length, in meters, of each of the following; (a) a mouse, (b)...

See similar textbooks

Similar questions

Consider two identical springs. This means that the two springs are made of the same wire, have the same diameter and number of coils and have the same un-stretched length which is equal to 10 cm. During operation, both springs work within their linearly elastic range. Spring A operates between 10 cm and 20 cm. Spring B operates between 15 cm and 25 cm. Which spring has the larger change in energy moving between its extreme operating points?
A 54-kg box is being pushed a distance of 7.2 m across the floor by a force whose magnitude is 167 N. The force is parallel to the displacement of the box. The coefficient of kinetic friction is 0.20. Determine the work done on the box by each of the four forces that act on the box. Be sure to include the proper plus or minus sign for the work done by each force.
A 56.4-kg box is being pushed a distance of 7.11 m across the floor by a force P whose magnitude is 186 N. The force P is parallel to the displacement of the box. The coefficient of kinetic friction is 0.212. Determine the work done on the box by each of the four forces that act on the box. Be sure to include the proper plus or minus sign for the work done by each force. (a) Wp = (b) Wf= (c) Wmg= (d) WN= i i i i
A block of mass 2.80 kg is placed against a horizontal spring of constant k = 745 N/m and pushed so the spring compresses by 0.0550 m. HINT (a) What is the elastic potential energy of the block-spring system (in J)? When a spring is compressed or stretched, the spring potential energy, PEs = 1 2 kx2, is always positive. Gravitational potential energy, PEg = mgy, can be positive or negative depending on whether an object is above or below the y = 0 reference height. J (b) If the block is now released and the surface is frictionless, calculate the block's speed (in m/s) after leaving the spring. m/s
An m = 5.5kg box rests on a horizontal frictionless surface and is attached to a spring with spring constant k = 730 N/m. The spring is fixed at its other end and is initially at its natural (uncompressed) length. A horizontal force of F = 45 N is now applied to the box in a direction which extends the spring. [Recommended time : 10-12 minutes] a) The work done by the force, F. when the box has moved Ax = 10 cm is (J) a. 4.50 b. 4500 c. 730 d. 0.50 b) The potential energy of the spring when the box has moved Ax = 10 cm. (J) a. 36.50 b. 3.70 c. 12.20 d. 0.10
A 31 kg child uses a pogo stick to bounce up and down. The spring constant, k, of the toy equals 8,700 N/m. (a) By how much would the spring be compressed by the child if she simply balanced herself vertically on the pedals of the stick? (Give your answer in cm.) cm (b) How much energy (in J) is stored in the spring under this circumstance? J
A typical muscle fiber is 2.0 cm long and has a cross-section area of 3.1 x 10-9 m2. When the muscle fiber is stimulated, it pulls with a force of 1.2 mN. What is the work done by the muscle fiber as it contracts to a length of 1.6 cm?
When the load on a wire is increased slowly from 1 kg wt to 2 kg wt the elongation increases from 0.2 mm to 0.3 mm. How much work is done during the extension ? (g = 9.8 m/s²) (a) (c) f 1.96 × 10-³ J (b) 19.6 × 10³ J 0.196 × 10-³ J (d) 16 × 10-³ J
A Jack-in-a-box is a children's toy, where a doll (the "jack"), attached to a compressed spring, is secured in a closed box. The box is resting on a smooth horizontal surface when it is knocked over, causing the lid of the box to open. The energy stored in the spring is released and the doll is propelled out of the box along the horizontal surface. If the spring has a spring-constant 36 N/m, how much energy (in Joules) was stored in the spring if the base of the doll moves 0.9 m out of the box.
A box with with a mass m = 2kg is being pushed up a ramp by an unknown pushing force Fp. The coefficient of static friction between the box and interface is 0.7. The coefficient of kinetic friction between the box and interface is 0.6. The incline of the ramp is 15 degrees. The velocity of the box is constant. The surface of the ramp is 12 m. What is the work done by normal force while the box is being pushed the entire length of the ramp? [ I think that it is 0 N, since the x component of normal force which is parallel to motion is 0. Is that correct?]
How much work is done stretching Achilles tendon from rest by 1 cm? Tendon stiffness is 287 500 N/m.
A trunk of mass m = 0.6 kg is pushed a distance d = 30 cm up an incline with an angle of inclination theta = 23.0° by a constant horizontal force P = 425 N (see figure). The coefficient of kinetic friction between the trunk and the incline is 0.31. P. Calculate the work done on the trunk by the applied force P. Calculate the work done on the trunk by the frictional force. Calculate the work done on the trunk by the gravitational force.