A5 kg ball falls from rest from a height of 20 m. Determine the ball's potential and kinetic energy at point A shown in the picture.

The particles of an ice cube at 0°c (represented by the blue circles) come in contact with the particles of juan’s hand at 37°c (represented by the orange circles). which diagram correctly represents the temperature of the two substances and the direction of heat flow?

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The ratio of lift to drag l/d for a wing or airfoil is an important aerodynamic parameter, indeed, it is a direct measure of the aerodynamic efficiency of the wing. if a wing is pitched through a range of angle of attack, l/d first increases, then goes through a maximum, and then decreases. consider an infinite wing with an naca 2412 airfoil. estimate the maximum value of l/d. assume that the reynolds number is 9x10^6.