An object 1.05 cm tall is 80 cm away from the screen and the size of its image an the screen is 0.35 cm Find the position and focal length of the lens.

Two large, flat, horizontally oriented plates are parallel to each other, a distance d apart. half way betwween the two plates the electric field has magnitude e. if the separation of the plates is reduced to d/2 what is the magnitude of the electric field half way between the plates?

If forces acting on an object are unbalanced, which factors may result fron an unbalanced force? check all that apply

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