You have just put some medical eyedrops on your sensitive eyes. The cornea has an index of refraction of 1.38, while the eye drops have a refractive index of 1.45. After you put in the drops, your friends notice that your eyes look red, becuase red light of a wavelength of 600 nm has been reinforced in the reflected light.

(a) What is the minimum thickness of the film of eyedrops on your cornea?

(b) Will any other wavelengths of visible light be reinforced in the reflected light? Will any be cancelled?

(c) Suppose you had contact lenses, so that the eyedrops went on them instead of your corneas. If the refractive index of the lens material is 1.50 and the layer of eyedrops has the same thickness in part (a), what wavelengths of visible light will be reinforced? What wavelengths will be cancelled?

An object moves from the position +34m to the position -15m in 15 seconds. what is it's total displacement? what is it's average velocity?

Part f - example: finding two forces (part i) two dimensional dynamics often involves solving for two unknown quantities in two separate equations describing the total force. the block in (figure 1) has a mass m=10kg and is being pulled by a force f on a table with coefficient of static friction îľs=0.3. four forces act on it: the applied force f (directed î¸=30â above the horizontal). the force of gravity fg=mg (directly down, where g=9.8m/s2). the normal force n (directly up). the force of static friction fs (directly left, opposing any potential motion). if we want to find the size of the force necessary to just barely overcome static friction (in which case fs=îľsn), we use the condition that the sum of the forces in both directions must be 0. using some basic trigonometry, we can write this condition out for the forces in both the horizontal and vertical directions, respectively, as: fcosî¸â’îľsn=0 fsinî¸+nâ’mg=0 in order to find the magnitude of force f, we have to solve a system of two equations with both f and the normal force n unknown. use the methods we have learned to find an expression for f in terms of m, g, î¸, and îľs (no n).

All the simple machines make work easier to do by changing the or of a force. a. size; type b. work; type c. size; direction d. type; direction