In the given figure, BC represents the unbroken part of the tree.
Point C represents the point where the tree broke and CA represents the broken part of the tree.
Triangle ABC, thus formed, is right-angled at B.
Applying Pythagoras theorem in Δ ABC,
\(AC^2= BC^2+ AB^2\)
\(AC^2= (5 m)^2+ (12 m)^2\)
\(AC^2= 25 m^2+ 144 m^2= 169 m^2\)
\(AC = 13\) \(m\)
Thus, original height of the tree = \(AC + CB = 13\) \(m + 5 \) \(m\)
= \(18\) \(m\)
Match the items given in Column I with one or more items of Column II.
Column I | Column II |
(a) A plane mirror | (i) Used as a magnifying glass. |
(b) A convex mirror | (ii) Can form image of objects spread over a large area. |
(c) A convex lens | (iii) Used by dentists to see enlarged image of teeth. |
(d) A concave mirror | (iv) The image is always inverted and magnified. |
(e) A concave lens | (v) The image is erect and of the same size as the object. |
- | (vi) The image is erect and smaller in size than the object. |