Name: ____Sarmeen Malek_________________________ Date: _ June_2 2020__
Student Exploration: Ray Tracing (Lenses)
Vocabulary: concave lens, convex lens, focal point,
image, magnification, real image, refraction, virtual
image
Prior Knowledge Questions (Do these BEFORE
using the Gizmo.)
Agnes is trapped on a desert island with nothing but
a magnifying glass. She wants to use the glass to
focus sunlight and start a fire. She holds the glass
above some dry grass as shown at right.
1. On the diagram, draw the path the Sun rays will
likely take from the magnifying glass to the
grass.
2. A magnifying glass is an example of a convex lens
—a lens that curves outward on both sides.
Why is a convex lens useful for starting fires? ____________________________________
_________________________________________________________________________
Gizmo Warm-up
The Ray Tracing (Lenses) Gizmo shows light rays passing
through a lens. The light rays are bent by refraction as they
pass through the lens and form a focused image to the right
of the lens.
To begin, turn on the Colorize lines checkbox. Under
Show lines, turn off the Central line and the Line through
focal point so that only the Parallel line is showing.
1. The blue dots in front of and behind the lens are the focal points of the lens. Move the
candle on the left back and forth and up and down.
What is always true about the light ray that emerges from the right side of the lens?
_________________________________________________________________________
2. Turn off the Parallel line and turn on the Line through focal point. Move the candle.
2019
, What do you notice about this line? _____________________________________________
_________________________________________________________________________
2019
Student Exploration: Ray Tracing (Lenses)
Vocabulary: concave lens, convex lens, focal point,
image, magnification, real image, refraction, virtual
image
Prior Knowledge Questions (Do these BEFORE
using the Gizmo.)
Agnes is trapped on a desert island with nothing but
a magnifying glass. She wants to use the glass to
focus sunlight and start a fire. She holds the glass
above some dry grass as shown at right.
1. On the diagram, draw the path the Sun rays will
likely take from the magnifying glass to the
grass.
2. A magnifying glass is an example of a convex lens
—a lens that curves outward on both sides.
Why is a convex lens useful for starting fires? ____________________________________
_________________________________________________________________________
Gizmo Warm-up
The Ray Tracing (Lenses) Gizmo shows light rays passing
through a lens. The light rays are bent by refraction as they
pass through the lens and form a focused image to the right
of the lens.
To begin, turn on the Colorize lines checkbox. Under
Show lines, turn off the Central line and the Line through
focal point so that only the Parallel line is showing.
1. The blue dots in front of and behind the lens are the focal points of the lens. Move the
candle on the left back and forth and up and down.
What is always true about the light ray that emerges from the right side of the lens?
_________________________________________________________________________
2. Turn off the Parallel line and turn on the Line through focal point. Move the candle.
2019
, What do you notice about this line? _____________________________________________
_________________________________________________________________________
2019
