Apowerboat is operating at night. which of these lights must be shown?

One day, after pulling down your window shade, you notice that sunlight is passing through a pinhole in the shade and making a small patch of light on the far wall. you see that the patch of light seems to be a circular diffraction pattern. it appears that the central maximum is about 1 cm across and you estimate that the distance from the window shade to the wall is about 3 m. what is (a) the average wavelength of sunlight? (b) the diameter of the pinhole?

What are similarities and differences between refraction, reflection, diffraction and absorption?

Chemical energy is a form of energy. a. heat b. kinetic c. potential d. electromagnetic