Saved Bookmarks
| 1. |
A mirror forms a real image twice the size of the object when placed 8cm in front of the mirror . find F of the mirror and its type . |
|
Answer» ve mirror BRU In the given problem, magnifiction ,m= - 2 (SINCE the image is inverted m is negative). m=hiho=−2 where 'hi' and 'ho' are HEIGHTS of the image and the object, respectively. m=−vu ∴M=vu=2 v=2u focal length of a concave mirror =- 8 cm. (USING sign convention) Form mirror formula, 1f=1u+1v 1−8=1u+12u −8=2u3 2u=3×(−8) u=3×−82=3×(−4)=−12 cm The object is placed at a distance of 12 cm from the pole of the concave mirror . Image distance v = 2u v=2×(−12) v=−24 cm . The image is FORMED at a distance of 24 cm from the ple, and is formed on the same side of the mirror where the object is kept. |
|