Reflection Basics
What happens when light bounces off a surface?
Reflection
Which type of surface produces regular reflection: smooth or rough?
Smooth surface
Is the image in a plane mirror upright or upside down?
Upright
How many plane mirrors are used in the simple periscope shown in the lesson?
Two
Pepper's ghost is an example of what type of visual effect?
An illusion
What do we call the light ray that travels toward a reflecting surface?
Incident ray
Which type of reflection occurs when light hits a rough surface?
Irregular reflection
Is your mirror image bigger, smaller, or the same size as you?
The same size
At what angle are the mirrors positioned in a simple periscope?
45°
Where is Pepper's ghost commonly used?
Theatres or amusement parks
What do we call the light ray that bounces away from a reflecting surface?
Reflected ray
In regular reflection, are the reflected rays parallel or scattered?
Parallel
What type of image is formed by a plane mirror: real or virtual?
Virtual
What scientific principle allows a periscope to work?
Reflection of light
What transparent material can be used to create the Pepper's ghost effect?
Transparent film or glass
What is the imaginary line drawn perpendicular to a reflecting surface called?
Normal
In irregular reflection, what happens to the reflected light rays?
They are reflected in different directions.
Can a virtual image formed by a plane mirror be captured on a screen?
No
How many times is light reflected inside the simple periscope?
Twice
Is the “ghost” seen by the audience a real object on the stage?
No
Between which two lines is the angle of incidence measured?
The incident ray and the normal
Would a plane mirror produce regular or irregular reflection?
Regular reflection
What is it called when the left and right sides of an image appear reversed?
Lateral inversion
Give one situation in which a periscope would be useful.
Seeing over a wall or obstacle.
What happens to some of the ghost-room light when it reaches the transparent glass?
It is reflected toward the audience.
Between which two lines is the angle of reflection measured?
The reflected ray and the normal
Why does a rough surface produce irregular reflection?
Its uneven surface reflects light in different directions.
You stand 3 m in front of a plane mirror. How far behind the mirror does your image appear?
3 m
After light enters the top of a periscope, what does it hit first?
The first/top plane mirror
Why does the ghost image appear translucent or “ghostly”?
Because reflected light from the hidden image combines with the view through the transparent glass.
If the angle of incidence is 35°, what is the angle of reflection?
35°
A beam of parallel light rays strikes a smooth, shiny surface. Predict what happens to the reflected rays.
They remain parallel and travel in the same direction.
An object moves 2 m closer to a plane mirror. What happens to the image?
The image also appears 2 m closer to the mirror.
After reflecting from the first mirror, where does the light travel?
Down the periscope toward the second mirror.
What happens to light from the stage when it reaches the transparent glass?
It passes through the glass to the audience's eyes
State the first law of reflection.
The incident ray, reflected ray and normal lie on the same plane.
Two surfaces are hit by identical parallel light rays. Surface A reflects them in one direction; Surface B scatters them. Which surface is rough?
Surface B
Why can't the image formed by a plane mirror be projected onto a screen?
Because it is a virtual image.
Why must the reflective sides of the mirrors face each other in the simple periscope?
So the light can reflect from the first mirror to the second mirror.
How is Pepper's ghost different from an ordinary plane-mirror image?
t uses transparent glass so transmitted stage light and reflected image light can both reach the audience.
State the second law of reflection using an equation.
Angle of incidence = angle of reflection (∠i = ∠r)
Explain the main difference between regular and irregular reflection.
Regular reflection sends rays in the same direction, while irregular reflection scatters them in different directions
Name four characteristics of an image formed by a plane mirror.
Upright, same size, laterally inverted, and virtual.
Describe the complete path of light through a simple periscope.
Light enters, reflects from the top mirror, travels down, reflects from the bottom mirror and enters the observer's eyes.
Explain how reflection and transmission work together to create the Pepper's ghost illusion.
Stage light passes through the transparent glass while some light from the hidden image is reflected by the glass toward the audience, making the virtual image appear on the stage.