A flat mirror that is 0.85m tall is attached to a wall so that its upper edge is 1.7m above the floor. Use the law of reflection and a ray diagram to determine if this mirror will show a person who is 1.7m tall his or her complete reflection.
I don't know how to draw it, the light reflected by the feet that is perpendicular to the mirror is not reflected as the mirror is too small, but how can I show this?
It does not matter how far away the person is standing (as long as it's not 0 distance!).
If you draw a ray from the top of the person to the mirror and back to the person, the point that the person sees is exactly twice as far down as where the reflection is in the mirror.
Since the mirror is 1/2 has tall as the person, it will thus reflect the entire 1.7m of the person.
You don't care about points that are perpendicular to the mirror, just know that the angles of incidence and reflection are equal.
Well, let me help you visualize it in a humorous way. Imagine the mirror is a tiny magician who only performs half of the reflection trick. The mirror raises its magic wand and says, "Abracadabra, I shall reflect all but your feet!" And poof! Just like that, your feet vanish from the reflection like a disappearing act.
So, when a 1.7m tall person stands in front of this mirror, they will see their entire body except for their feet, which will be missing from the reflection. It's like the mirror is playing a silly game of hide-and-seek with your feet. Just remember not to wear any fancy shoes that you want to show off!
Now, when it comes to the ray diagram, draw a person, but only draw their upper body in the reflection, with their feet cut off. The ray of light from the person's feet that's perpendicular to the mirror should be shown as not getting reflected, just extending beyond the mirror as if they're taking a leap of faith into the unknown.
I hope this helps you understand how the mirror will show a person their incomplete reflection. Feel free to ask if you have any more mirror-related riddles for me to solve!
To determine if the mirror will show a person who is 1.7m tall their complete reflection, we can use the law of reflection and a ray diagram.
1. Begin by drawing a diagram of the mirror against the wall. Draw a straight vertical line to represent the mirror, and label its height as 0.85m. Above the mirror, draw another straight line to represent the upper edge of the mirror, which is 1.7m above the floor.
2. Draw a person standing in front of the mirror, represented as a vertical line with a height of 1.7m.
3. Draw a ray of light coming from the top of the person, parallel to the person's vertical line. This ray will hit the mirror at a point above its upper edge.
4. According to the law of reflection, the angle of incidence (the angle between the incident ray and the normal line to the mirror) is equal to the angle of reflection (the angle between the reflected ray and the normal line to the mirror).
5. Draw a normal line on the mirror, which is a perpendicular line to the mirror's surface at the point where the ray of light hits the mirror.
6. Draw the reflected ray of light, which should be directed downward at the same angle as the incident ray. Extend this ray to see if it hits the person's feet.
7. In this case, since the mirror is smaller than the person's height, the reflected ray will not reach the person's feet. Instead, it will hit the floor in front of the mirror.
8. Thus, the mirror will not show the person's complete reflection since the reflected ray does not reach the person's feet. The upper portion of the person will be visible in the mirror, but the lower portion will not be reflected.
So, the mirror will not show a person who is 1.7m tall their complete reflection.
To determine if the mirror will show a person who is 1.7m tall their complete reflection, we can use the law of reflection and draw a ray diagram.
Law of Reflection:
According to the law of reflection, the angle of incidence (θi) is equal to the angle of reflection (θr), and both angles are measured with respect to the normal line perpendicular to the mirror surface.
Ray Diagram Steps:
1. Draw a line perpendicular to the mirror at the point where the mirror meets the floor. This line is called the normal.
2. Draw a person who is 1.7m tall in front of the mirror, with their feet touching the floor.
3. Draw a ray of light from the person's eyes to the mirror. This ray strikes the mirror surface at an angle of incidence (θi).
4. Use the law of reflection to draw the reflected ray. The angle of reflection (θr) will be equal to the angle of incidence (θi), measured with respect to the normal.
5. Continue drawing the reflected ray until it intersects with the mirror.
6. Mark the point where the reflected ray intersects the mirror as point A.
7. Draw a line from the person's feet through point A. This represents the path of light reflected from the person's feet.
8. Determine where this line intersects the mirror and mark it as point B.
9. Measure the vertical distance between points A and B. If this distance is greater than the height of the mirror (0.85m), it means the mirror will show the person's complete reflection. If the distance is less than 0.85m, the person's complete reflection will not be visible in the mirror.
By following these steps and drawing the ray diagram, you can determine if the mirror will show a person who is 1.7m tall their complete reflection.