kwizNET Subscribers, please login to turn off the Ads!
Email us to get an instant 20% discount on highly effective K-12 Math & English kwizNET Programs!

Online Quiz (Worksheet A B C D)

Questions Per Quiz = 2 4 6 8 10

Upper Elementary Science - II
4.3 Lenses

When you put a pencil in a half glass of water what happens? The pencil appears to be crooked. Whenever you see something, you are seeing light rays reflected from the object. In the case of the pencil, the light reflected from it travels through the water and the glass, then through the air, before it reaches your eyes. The light rays change the path just a little when they move from water to glass, then from glass to air. Those slight changes in the path of the light rays between the pencil and your eyes make the pencil look crooked under water.

Sometimes we want to change the path of light rays coming from the things we are viewing in order to see them better. For that, we use things called lenses.

A lens is a curved piece of transparent material, usually glass or plastic. It is said that the lens bends the light but actually, the curve of the lens makes the light rays change their path. Thatís how a magnifying glass works. When you hold a magnifying glass at the right distance from a book, the words come in to focus and look bigger. The light rays coming from the page of the book have traveled through the lens glass and changed their path slightly to appear larger to your eyes.

Lenses can make things look bigger or smaller. Binoculars use lenses to make faraway things look bigger. But when you look through binoculars backward, they make things appear smaller.

Because of lenses we can see the world better than what we could see with only our eyes. Lenses in telescope help us see faraway, as far away as the moon, planets, and stars. Lenses in microscope help us see tiny things close-up, including things we cannot see with our eyes alone, such as the cells in our body or the little creatures that live in a drop of pond water.


Directions: Answer the following questions.
Q 1: _____________ use lenses to make faraway things look bigger.
Plain glass
Binoculars

Q 2: When looked through binoculars backward, they make things appear bigger.
false
true

Q 3: The cells in our body or the little creatures that live in a drop of pond water are seen with -
telescope
microscope

Q 4: Whenever we see something we are seeing the light rays reflected from the object.
true
false

Q 5: A curved piece of glass or plastic-
telescope
lens

Q 6: Lenses are used to see things better than how they appear to us.
true
false

Q 7: Lenses in _________ help us see faraway, as far away as the moon, planets, and stars.
telescope
microscope

Q 8: ______________ makes the light rays change their path.
The lens
The curve of the lens

Question 9: This question is available to subscribers only!

Question 10: This question is available to subscribers only!


Subscription to kwizNET Learning System offers the following benefits:

  • Unrestricted access to grade appropriate lessons, quizzes, & printable worksheets
  • Instant scoring of online quizzes
  • Progress tracking and award certificates to keep your student motivated
  • Unlimited practice with auto-generated 'WIZ MATH' quizzes
  • Child-friendly website with no advertisements
  • Choice of Math, English, Science, & Social Studies Curriculums
  • Excellent value for K-12 and ACT, SAT, & TOEFL Test Preparation
  • Get discount offers by sending an email to discounts@kwiznet.com

Quiz Timer