TED Talk Quiz:
Adjustable Liquid-Filled Glasses

Print out the quiz or simply write the answers on a piece of paper. The answers are given at the bottom of the page

Quiz Questions

1.  Joshua Silver talks about one of the world’s largest problems. He also says he knows an answer to this problem and talks about how this problem can be solved.

a.  True

b.  False


2.  The World Health Organization has different estimates about how many people in the world who need glasses ranges from 150 million to one billion.

Joshua Silver believes that the need for corrective eyeglasses (to improve vision) is about:

a.  1/8 the population

b.  1/4 the population

c.  1/2 the population

d.  3/4 the population

e.  everyone


3.  Joshua Silver says that the problem of poor vision is not just a health problem.  It’s also an:

a.  An educational problem

b.  An economic problem

c.  A quality of life problem

d.  a and b above

e.  a, b and c above


4. The reason that half the population does not have corrective eyeglasses is because:

a.  There is a shortage of eye care professionals

b.  Glasses are expensive

c.  There is a shortage of eye glasses


5.  Joshua Silver explained that in in some countries in sub-Saharan Africa, there’s just one optometrist for every:

a.  8 million people

b.  800,000 people

c.  80,000 people

d.  8,000 people


6.  Joshua Silver’s solution is based on “adaptive optics,” which means that the person can adapt the glasses themselves by adjusting the liquid on each side of the lens.

a.  True

b.  False


7.  Joshua has been working on this project since 1985 and the work has been going very slowly. There are about 30,000 of his glasses in use now in 15 countries. He wants to spread them around the world to ______________ people.

a.  300,000

b.  8 million

c.  1 billion

d.  8 billion


8.  The pair of glasses that Joshua Silver showed the audience cost about 19 dollars, which is very cheap. He says that’s not cheap enough; the cost has to be reduced even more.

a.  True

b.  False

Quiz Answers

1.  a

2.  c

3.  e

4.  a

There are enough eye glasses, however, there aren’t enough eye care professionals to help people with prescription glasses.

5.  a

6.  a

7.  c

8.  a

It has to be brought down because he’s trying to serve populations who live on a dollar a day.


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