ABO exam prep part 2 Questions And Answers Graded A+

The basic definition of a prism may be expressed mathematically as: - 1cm/1m=1 prism Prentice's Rule states that the amount of induced prism equals to - Power of the lens times the decentration in millimeters divide by 10 (prism= F x dec (mm) divided by 10) A minus lens gets ________ the closer to the eye. - stronger Axis is _______________________. - a notation of position in relation to the cornea and the corrective lens. Axis notations have no value. Decentering a minus lens outward will result in - Base in prism Decentering a minus lens upward will result in - Base down prism Decentering a plus lens inward will result in - Base out prism Decentering a plus lens upward will result in - Base up prism Eyeglass prescription powers are written in ___________________. - Diopters High plus lenses create a peripheral distortion that causes objects to appear in what shape? - Pincushion If a converging lens has a focal length of +2 meters, its power is - Using formula (D=1/F) D=1/+2 D=+0.50 m or +50cm or +500mmIf a prism can displace an image one centimeter at a distance of one meter, it is said to have a power of - 1 prism diopter and the formula looks like this, 1cm/1m=1prism If needed, prescriptions are written with an axis between ___________________. - 0-180 In a minus powered lens light rays ____ and come to a focal point ____ the lens. - Diverge, in front of A diverging lens produces a ________ image. - Virtual When the direction of light is divided in the course of passing from one transparent medium to another is known as: - Refraction In simple terms all lenses are really ______________. - prisms Light passing through a minus lensis said to be ___________. - diverging Light passing through a plus lens is said to be ___________ . - converging Light rays pass through a lens and converge at a point 50cm behind the lens, what is the power? - D=1/f D=1/50 D=+2.00 Light travels through a certain transparent medium at the rate of approximately 109,412 miles per second. The index of refraction of this medium is - N(index of refraction)= speed of light in air/ Speed of light in the material N=186,000/109,412 N=1.70 One meter is equal to ___________ inches. - 39.37One of the ways of identifying a lens with minus power is to look for - Objects seen through the lens seem to move in the same direction as the lens is moving One prism diopter deviates a ray of light_______ . - 1 cm at a distance of 1 meter Prentice's Rule states: - The power of the prism is equal to the power of the lens in diopters times the amount of decentration in millimeters divided by 10. Rays emanating from a point source of light are said to be - Diverging Snell's law is: - ni (sin < i) = nr (sin < r) steps of flat transposition are - 1)add the cylinder power to the sphere power algebraically. 2)change the sign of the cylinder leaving the power the same 3)move the axis by 90 degrees while staying between 0-180 The ___________ theory describes light as traveling through space in minute bursts of energy. - Corpusclar The _____________ Theory describes light as moving in waves. - Wave The density of any given material can be expressed as - Index of refraction