Answer:
Explanation:
There will be reaction force by each vertical post on horizontal plank . Let it be R₁ and R₂ . R₁ is reaction force by the post nearer to woman
Taking torque of all forces about the end far away from the woman
Torque by reaction force = R₁ x 5.5
= 5.5 R₁ upwards
Torque by weight of woman in opposite direction , downwards
= - 804 x ( 5.5 - 1.55 )
= - 3175.8
Torque by weight of the plank in opposite direction , downwards .
= - 27 x 5.5 / 2
= - 74.25
Torque by R₂ will be zero as it passes through the point about which torque is being taken .
Total torque
= 5.5 R₁ - - 3175.8 - - 74.25 = 0 ( For equilibrium )
5.5 R₁ = 3250
R₁ = 590.9 N .
Answer:
3050.6 Litre .
Explanation:
Total time of heart beat = Total time of race = 2 hrs , 39 minutes and 54 seconds
= 2 x 60 + 39 + 54/60 min
= 120 + 39 + .9 min
= 159.9 min
rate of heart beat = 170 per min
Total no of heart beat during race = 170 x 159.9
volume of blood per kg per beat = 2.5 mL per kg of weight
body weight = 99 pounds = .4535 x 99 kg = 44.89 kg
volume of blood per beat = 2.5 mL x 44.89 mL
= 112.225 mL .
Total required volume of blood = 112.225 x 170 x 159.9 mL
= 3050612 mL
= 3050.6 L.