After a laser bean passes through two thin parallel slits, thefirst completely dark fringes occur at ± 15.00with the original direction of the beam, as veiwed on a screen farfrom the slits.
(a) what is the ratio of the distance between the slits to thewavelength of the light illuminating the slits?
(b) what is the smallest angle, relative to original directionof the laser beam, at which the intensity of the light is 1/10 themaximum intensity on the screen?

An engineer designs a roller coaster so that a car travels horizontally for 162 ft, then climbs 127 ft at an angle of 31.0° above the horizontal. it then moves 127 ft at an angle of 46.0° below the horizontal. if we take the initial horizontal motion of the car to be along the +x-axis, what is the car's displacement? (give the magnitude of your answer, in ft, to at least four significant figures and give the direction of your answer in degrees counterclockwise from the +x-axis.)

Afeather of mass 0.001 kg falls from a height of 2 m. under realistic conditions, it experiences air resistance. based on what you know about friction, what can you say about the kinetic energy of the feather as it reaches the ground? acceleration due to gravity is g = 9.8 m/s2. a. ke < 0.0196 j b. ke = 00196 j c. je = 0 j d. ke > 0.0196 j

Which pair of quantities includes one quantity that increases as the other decreases during simple harmonic motion?