subject
Physics, 21.11.2019 04:31 felipe9086

If a person of mass m simply moved forward with speed v, his kinetic energy would be 12mv2. however, in addition to possessing a forward motion, various parts of his body (such as the arms and legs) undergo rotation. therefore, his total kinetic energy is the sum of the energy from his forward motion plus the rotational kinetic energy of his arms and legs. the purpose of this problem is to see how much this rotational motion contributes to the person's kinetic energy. biomedical measurements show that the arms and hands together typically make up 13.0 % of a person's mass, while the legs and feet together account for 37.0 %. for a rough (but reasonable) calculation, we can model the arms and legs as thin uniform bars pivoting about the shoulder and hip, respectively. in a brisk walk, the arms and legs each move through an angle of about ±30∘ (a total of 60∘) from the vertical in approximately 1 second. we shall assume that they are held straight, rather than being bent, which is not quite true. let us consider a 79.0-kg person walking at 5.50 m/s having arms 68.0 cm long and legs 93.0 cm long.1-what is the average angular velocity of his arms and legs? 2-using the average angular velocity from part a, calculate the amount of rotational kinetic energy in this person's arms and legs as he walks.3-what is the total kinetic energy due to both his forward motion and his rotation? 4-what percentage of his kinetic energy is due to the rotation of his legs and arms?

ansver
Answers: 2

Another question on Physics

question
Physics, 21.06.2019 20:20
How much work would a child do while puling a 12-kg wagon a distance of 3m with a 22 n force directed 30 degrees with respect to the horizontal? (a) 82j (b) 52j (c) 109j (d) 95j
Answers: 2
question
Physics, 22.06.2019 04:00
Assume similar data for the motion of the blood in your aorta. estimate how many beats of the heart it will take the blood to get from your heart to your brain. (assume that the distance from your heart to your brain is 30 cm)
Answers: 2
question
Physics, 22.06.2019 04:30
True or false when elements combine to form a mixture, the resulting chemical properties may be very different from those of the elements that make it.
Answers: 2
question
Physics, 22.06.2019 11:30
A100-watt light bulb illuminates a solar cell. the electricity from the solar cell operates a water pump that delivers 1 watt of power. what is the efficiency of the system?
Answers: 2
You know the right answer?
If a person of mass m simply moved forward with speed v, his kinetic energy would be 12mv2. however,...
Questions
question
Mathematics, 22.06.2019 01:10
question
Mathematics, 22.06.2019 01:10
question
Chemistry, 22.06.2019 01:10