 |
| Construction - 10 |
|
|
| |
| In Physics, we study reflection and the image formed by a plane mirror. We specially notice two properties of the image: |
| |
| (i) The image is as much behind the mirror as the object is in front of it. |
| |
| (ii) The mirror is the perpendicular bisector of the line joining the image and the object. |
| |
| XY is the mirror. |
| |
| P is the object and I the image. |
| |
| XY is the perpendicular bisector of PI. |
| |
 |
| |
|
| |
 |
| |
| A line XY and a point P outside it. |
| |
 |
| |
| The reflection of P in XY. |
| |
 |
| |
 |
| |
| (i) Construct a perpendicular from P to XY to meet XY at M. |
| |
| (ii) Produce PM to P' such that PM = P'M. |
| |
| Then, P' is the image of P in XY. |
| |
 |
| |
| If point P is on XY, then P itself is the image. |
| |
|
| |
|
|
| |
| A line XY and a line AB. |
| |
|
|
| |
| The reflection of AB in XY. |
| |
 |
| |
 |
| |
| (i) From A, construct AM ^ XY and produce it. |
| |
| (ii) Obtain point A' (the reflection of A in XY) on the other side of XY, so that AM = A'M. |
| |
| (iii) Similarly, from B, construct BN ^ XY and produce it. |
| |
| (iv) Obtain point B' (the reflection of B in XY) on the other side of XY, so that BN = B'N. |
| |
| (v) Join A'B'. |
| |
| (vi) \A'B' is the reflection of AB in XY. |
| |
|
| |
|
|
| |
| A point A and a point M. |
| |
| We are required to construct the reflection of point A through a point M. |
| |
 |
| |
| (i) Join AM and produce it. |
| |
| (ii) Obtain point A' on the line so that AM = A'M. |
| |
| (iii) Then A' is the image of A in point M. |
| |
 |
| |
|
| |
|
|
| |
| A line AB and a point O. |
| |
| We are required to reflect AB through O. |
| |
 |
| |
 |
| |
| (i) Join AO and produce it to A', so that AO = A'O. |
| |
| (ii) Similarly, join BO and produce it to B', so that BO = B'O. |
| |
| (iii) Join A'B'. |
| |
| Then A'B' is the image of AB in O. |
| |
