Science - Using a hand lens (Information sheet and Investigation)
A magnifying glass is also known as a hand lens in a laboratory context. It is a convex lens that produces a magnified image of an object.
How does a magnifying glass work?
Below is a video you can show to your learners to best explain how a magnifying glass works.
We use a magnifying glass to investigate, to enhance an object, to gain more information.
What is the difference between a convex and a concave lens?
Convex lenses are thicker at the middle. ... Rays of light that pass through the lens are spread out (they diverge). A concave lens is a diverging lens. When parallel rays of light pass through a concave lens the refracted rays diverge so that they appear to come from one point called the principal focus.
https://www.quora.com/What-are-the-difference-between-convex-lens-and-concave-lens
Investigation
Using a hand lens
APPARATUS
• a hand lens (will be provided in class)
• a sharp pencil
• a ruler
ASSIGNMENT
- Go outside on the school grounds and collect different small objects such as insects, twigs, flowers or leaves.
- Choose four (4) objects and observe them with the naked eye. Draw what you see. Write a brief description of your observations.
- Now examine the same objects with the hand lens. Now draw what you see and give a brief description of your observations.
- Compare what you saw through the hand lens with what you saw without the hand lens.
- Estimate the magnification of the objects in your drawings.
- Use the ruler to measure each of your drawings. Measure the actual length of each object. Calculate the magnification of the objects in your drawings. (Show your working).
OBSERVATIONS (Learner writes their observations down)
Interesting videos on hand lenses
Baie oulik