What is the average angular velocity of his arms and legs

Assignment Help Physics

Reference no: EM13313291

If a person of mass M simply moved forward with speed V, his kinetic energy would be1/2 MV^2. 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 14.0\% of a person's mass, while the legs and feet together account for 38.0\% . 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 \pm 30\;^\circ (a total of 60\;^\circ) 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 75.0{\rm kg} person walking at 5.00{\rm km/h} having arms 70.0{\rm cm} long and legs 92.0{\rm 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?

Reference no: EM13313291

Questions Cloud

Determine change in the bottom elevation and water surface : A hydraulic transition 100 ft long is used to connect two rectangular channels, 12ft and 6ft wide. The design discharge is 500 cfs, mannining coefficient=.013 and the slopes of the channels are both .0009.

Compute the energy difference (e) for the transition : Calculate the energy difference (E) for the transition from n = 1 to n = 4 energy levels of hydrogen per 1 mol of H atoms.

Find the takeoff speed of the froghoppper : An average froghopper insect has a mass of 12.3 mg and reaches a maximum height of 290 mm when its takeoff angle is 58 degrees above the horizontal. Find the takeoff speed of the froghoppper

Determine what is the anle of internal friction for the sand : a direct shear cell 25.4cm x 25.4 cm in plan is filled with dry sand. a normal load of 6kN is applied to the sample, and the shear failure is 3.5kN. What is the anle of internal friction for the sand

What is the average angular velocity of his arms and legs : If a person of mass M simply moved forward with speed V, his kinetic energy would be1/2 MV^2. However, in addition to possessing a forward motion, What is the average angular velocity of his arms and legs

Explain what is the ph of 0.00135 mol/l h2so4(aq) : Sulfurous acid, H2SO3, is a weak diprotic acid (pKa,1=1.89 and pKa,2=7.21 at 25oC). What is the pH of 0.121 mol/L H2SO3(aq) at 25oC? Give your answer accurate to two decimal places.

Describe a client or server protocol used in everyday life : Suppose a time-sharing operating system allocated time slices of 20 milliseconds and the machine executed an average of 5000 instructions per microsecond. How many instructions could be executed in a single time slice?

Enforcement of regulation for all business entities : Should Australia's regulatory and administrative bodies be further harmonised to create one ‘super' regulator for design and enforcement of regulation for all business entities?

Will the quantity of coarse aggregate increase or decrease : Compute the required weight of coarse aggregate per cubic yard. to adjust the mix so as to increase the compressive strength, the water-to-cement ratio is reduced to 0.45. will the quantity of coarse aggregate increase, decrease, or stat the same

User Account

All Pages