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juan uses a lever to lift a rock. he places the rock on the short arm of the lever and pushes down on the other arm of the lever. he applies 30 n of force over a distance of 1 m. the other end of the lever moves in the opposite direction and raises the rock a distance of 0.2 m. what is the weight (force) of the rock
what is the mechanical advantage of the lever in question 1?

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.

Look at the electroscope, describe how you can cause the two leaves at the bottom to repel each other and stay that way

The goal of this experiment was to answer the question, "how does diffraction occur? " suppose you formulated this alternate hypothesis: if the gap width is increased while keeping wavelength constant, then the observed diffraction will decrease because the less the ratio between wavelength and gap width is, the smaller the observed diffraction angle will be.to test this hypothesis, you would change the  gap widthdiffraction anglewavelength  and observe the  gap widthdiffraction anglewavelength  in the system.therefore, the independent variable would be the  gap widthdiffraction anglewavelength  and the dependent variable would be the  gap widthdiffraction anglewavelength.