] Light of wavelength 500.0 nm in air falls at normal incidence on an oil film that is 850.0 nm thick. The oil is floating on a water layer. The refractive index of water is 1.33, and that of the oil is 1.40. You want to add oil so that light reflected from the oil film will be canceled. What is the minimum thickness of oil film you need to add

Adding more pulleys to a system of pulleys needed to lift an object. a. increases the force b. decreases the force c. increases the amount of work d. decreases the amount of work

Unpolarized light of intensity i_0=750w/m^2 is incident upon two polarizers. after passing through both polarizers the intensity is i_2=280w/m^2. (a) what is the intensity of the light after it passes through the first polarizer in w/m^2? (b) write an equation for the angle between the polarizers in terms of the initial (i_0) and final (i_2) intensities. (c) find the angle between the polarizers in degrees.

Polly is pushing a box across the floor with a force of 30 n. the force of gravity is –8 n, and the normal force is 8 n. which value could describe the force of friction if polly could not move the box?