While unrealistic, we will examine the forces on a leg when one falls from a height by approximating the leg as a uniform cylinder of bone with a diameter of 2.3 cm and ignoring any shear forces. Human bone can be compressed with approximately 1.7 × 10^8 N/m^2 before breaking. A man with a mass of 80 kg falls from a height of 3 m. Assume his acceleration once he hits the ground is constant. For these calculations, g = 10 m/s^2.
Requried:
a, What is his speed just before he hits the ground?
b. With how much force can the "leg" be compressed before breaking?
c. If he lands "stiff legged" and his shoes only compress 1 cm, what is the magnitude of the average force he experiences as he slows to a rest?
d. If he bends his legs as he lands, he can increase the distance over which he slows down to 50 cm. What would be the average force he experiences in this scenario?
e. Dyne is also a unit of force and 1 Dyn= 10−5 N. What is the maximum a bone can be compressed in Dyn/cm2?
f. Which of the following is the reason that we would recommend that the man bend his legs while landing from such a fall?
Answers: 1
Physics, 23.06.2019 02:30
Asatellite that goes around the earth once every 24 hours iscalled a geosynchronous satellite. if a geosynchronoussatellite is in an equatorial orbit, its position appearsstationary with respect to a ground station, and it is known as ageostationary satellite find the radius rof the orbit of a geosynchronous satellite that circles the earth.(note that ris measured from the center of the earth, not the surface.) you mayuse the following constants: the universal gravitational constant g is 6.67 \times 10^{-11}\; {\rm n \; m^2 / kg^2}. the mass of the earth is 5.98 \times 10^{24}\; {\rm kg}. the radius of the earth is 6.38 \times 10^{6}\; {\rm m}.
Answers: 2
Physics, 23.06.2019 05:00
Which of the following is a transformer used for? alternate a voltage produce a voltage increase or decrease a voltage eliminate a voltage
Answers: 1
Physics, 23.06.2019 07:30
What is the momentum of a 47-gram tennis ball that is traveling at 40 m/s
Answers: 2
While unrealistic, we will examine the forces on a leg when one falls from a height by approximating...
Mathematics, 19.04.2021 22:40
Mathematics, 19.04.2021 22:40
Mathematics, 19.04.2021 22:40
Mathematics, 19.04.2021 22:40
Mathematics, 19.04.2021 22:40
Biology, 19.04.2021 22:40
Mathematics, 19.04.2021 22:40
English, 19.04.2021 22:40
Mathematics, 19.04.2021 22:40
History, 19.04.2021 22:40
Mathematics, 19.04.2021 22:40