automobile mirrors?

Question

On most automobile passenger-side and rearview mirrors, a warning is printed: “Objects in mirror are closer than they appear.” Why this and what is makes the difference? Hint: the mirrors are convex mirrors

Answer 1

I remember this from high school physics. Practically the first day.

Mostly the label is there as an idiot lawyer label so you can't sue.

Not many vehicles have convex mirrors. Mostly large trucks have them. Yet, cars, all with normal mirrors have this warning and all in the passenger side mirror. Durring lunch I was in 2 parking lots anyway, so I looked. One car had a convex mirror, yet all cars had warnings. One truck had a convex mirror in the driver's side, yet the warning was in the passenger mirror.

The clue is what you state - it is only (mostly) on the passenger side mirror. If you look a lot in your driver side mirror an object will appear closer to you. An occasional check into the passenger side and it looks slightly further away. Why? Because the mirror is further way. The mirror can be 2 to 5 feet further away from you. Thus an image of an object you see in it appears 2 to 5 feet further back. Not much, unless you are trying to merge into a space with only 1.5 feet.

You will judge the distance as the distance from your eye to the mirror, plus the mirror to the object. So the warning can appear in any mirror as distanse to each mirror is different.

Don't just dismiss this answer, it is right and you can test it. Check out the 2 sides of the car to see if there is any difference in them. Then look in both mirrors and notice that things look further away in the further mirror. Even reverse it, sit in the passenger side and things look further away in the driver's side mirror.

If you doubt the math, here is another test. Have a friend about the same size as you stand face to face to you 4 feet appart. Now have her hold a mirror in front of her face. Your image in the mirror will be smaller. You will look like you are twice as far away. The image is of you 4 feet from the mirror, then you see the mirror 4 feet from you. You see an image similar to 8 feet away from you. Hold the mirror half way between you, 2 feet and the mirror image should look closer to the size of you friend .

That is the main reason, there are other effects. Like looking in a small mirror can create an illusion, and convex mirrors like you mention. But mostly a driver uses his side mirror most, and depending on individual habits and driving conditions, may only occasionally look at the passenger mirror. He better not treat the two as the same.

Answer 2

‘Objects in the mirror are closer than they appear”

Those who have studied Physics know that images of objects are seen in the mirror.

One will not call the image as object.

There are no objects inside the mirror only images are there.

The correct statement must be “Images in the mirror are closer than the real objects”.

Therefore, the above statement is not conveying the correct meaning and is a misleading one.

Further a warning is necessary, only if the images are farther away than the real objects.

If it were so, then there is a possibility of accident because of misjudgment of distance.

When images are closer than the real objects, no such warning is necessary.

In reality, because of this type of warning, a lay man may assume that the real objects are closer to him and in that case the warning does no purpose.

Answer 3

Hi. I think it was so Steven Spielberg could have a sight gag in the original Jurassic Park. The T. Rex was visible in the mirror and WAS close. The camera closed in the the words "Objects in mirror are closer than they appear.” (I assume you know all about diverging lens properties and your question was rhetorical!)

Answer 4

lol, I was about to spend time and think about the answer until I discovered that you know it and you're just testing us. You even give hints.

Answer 5

ithink you just answered yourself