Recent content by aopaop03

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    Max Accel for Pressure in Heart to Reach Brain

    A man is standing up in aircraft that has a constant accerelation upward. Find the maximum accerelation that heart can't pump blood to brain. Head is 50cm above the heart. Pheart=100mmHg ΣF=ma Fn-mg=ma Fn=m(g+a)=ρ(blood)V(g+a) Pfoot=ρ(blood)H(g+a) Pheart=Pfoot-ρ(blood)(H-0.5)(g+a) I don't know...
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    Can a Helium-Filled Weather Balloon Accelerate Upwards Faster Than Gravity?

    1. An empty spherical weather balloon with a mass of 5 kg has a radius of 2.879 m when fully inflated with helium. It is supposed to carry a small load of instruments having a mass of 10 kg. Taking air and helium to have densities of 1.16 kg/m^3, respectively, what will be the acceleration of...