Measuring density of parrallex objects

                           Normal line to

                                               mirror

                    Object Pins

                                    Plain paper

Method

1. Place the paper on top of the cork mat
2. Place the protractor on the left edge of the paper so you can make a 90o mark on the paper
3. Use the mark to draw a horizontal line across the paper using a ruler (this will be where you place your mirror)
4. Fix the mirror into the block and then attach some bluetak underneath it so it will stay affix
5. On the horizontal line make two normal mirror lines going vertically using the protractor (make them 90o  from the line and leave some space in between)
6. Place the mirror firmly on the horizontal line
7. Now place a needle on the first normal line and then place a second needle on the second normal line (make sure both of them are in front of the mirrors)
8. Move down so your eyesight is in level with the first needle and below the mirror
9. Pin your third needle down so it lines up with the first needle and when moving head side to side it looks as if it’s one needle
10. Do the same with the third needle, lining it with the second needle
11. When placing the third and fourth needle make sure that the pins are placed behind the mirror such that no parallax is observed when moving head left and right; the image in mirror and pin behind mirror is in vision

Results

A1- 3cm

A2- 5.1cm

A3- 3cm

A4- 5.6cm

A5- 7.5cm

A6- 7.6cm

Conclusion

The results show that A1 equals to A3 and A2 is similar to A4; this implies that the distance of image from the mirror line is the same as the distance of object from the same mirror line. A5 and A6 are also similar and this implies that the length of object is preserved in a plane; the length of image is the same as the length of the object (this doesn’t apply for concave or convex mirrors).

Evaluation

The results show that the experiment worked well as the two needles matched together (A1 and A3), although the rest weren’t exact matches they were really close and can see which one’s should’ve matched. These inaccuracies could’ve been created by many reasons such as human error, not lining up the needle accurately or not drawing the normal lines or mirror line perfectly at the right degree. This could also be due to the instruments that we had to do our experiment with such as the protractor was worn out so it was difficult to figure where to draw the right lines and also the width of the mirror at the top where I had to make my measurements from was too wide (about 3mm) so this may have caused a minor deviating measurement from the actual measurement.