Related Questions

Pharmacists recently conducted a study with respect to the reasons their customers purchased eye drops to soothe eye dryness. Dry eyes were more frequently experienced by customers who wore contact lenses than by custorners who did not wear contact lenses. The pharmacists concluded that wearing contact lenses, by itself, can cause contact wearers to have dry eyes.
A An inherited condition can cause both weak eyesight and dry eyes
B Physical exertion causes dry eyes in many people who wear contact lenses.
C Most people who have dry eyes do not wear contact lenses.
D Most people who wear contact lenses do not have dry eyes.
Contact lenses for eyes are made of perspex, which is nothing but
A Polymethylmethacrylate
B Polystyrene
C Unsaturated polyester
D Polypropylene
Contact lenses are worn in one's-
A cameras
B eyes
C shoes
D clothes
Bees have compound eyes - almost 6000 tiny lenses.
A made of
B made in
C made on
D made up
The computer has dramatically affected — photographic lenses are constructed.
A is the way
B that the way
C which way
D the way
Which of the following cannot be used for making lenses?
A Plastic
B Soil
C Glass
D Water
Plexiglass (also called lucite) because of its high optical transparency is used for making lenses. It is chemically
A Polymethyl methacrylate (PMMA)
B Polytetraflouroethylene(PTFE)
C Polycarbonates
D Phenolic resins
If points P and X are just meeting at the point of contact between the dials , and if dial 2 spins at exactly double the speed of dial 1, which of the following pairs of contact ?
A N and Y
B N and Z
C O and X
D O and Z
If points P and Y are just meeting at the point of contact between the dials , and if dial 1 spins at exactly three time the speed of dial 2, which of the following pairs of points will be the next pair to meet at the point of contact?
A N and X
B N and Z
C O and Y
D P and Z
Two circular dials of exactly the same size are mounted on a wall side by side in such a way that their perimeters touch at one point. Dial 1, which is on the left , spins clockwise around its center , and dial 2 , which is on the right spins counter clockwise around its center . (Assume that there is no friction at the point of contact between the dials.) Each dial is marked on its perimeter at three points that are at equale distances around the points arked ondial 1 are N, O, and P and the points marked on dial 2 are X, Y, and Z. If points O and Z are just meeting at the point of contact between the dials , and if dial 1 spins at the same speed as dial 2, what is the smallest number of revolutions of each dial that will bring O and Z together again?
A 1
B 2
C 3
D 4

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