DEVELOPMENT OF SURFACES

Ex:1 A pentagonal prism of base 30mm and axis 75 mm is resting on H.P on its base such that a base edge is perpendicular to V.P. A section plane cuts the axis of the prism at a distance of 18 mm from the top face and at angle of 45º with the horizontal. Draw the development of the truncated prism

1’5’ 2’4’ 3’ M 1 2 m 3 m 4 5 1 75 K k k T H h h X Y b’d’ c’ a’e’ A 30 18 K k k T H h h X Y b’d’ c’ a’e’ 30 A 30 B C D E A 4 a b c d e 5 3 1 2

Ex:2 A hexagonal pyramid of base 40mm and axis 120 mm is resting on H.P on its base such that a base edge is perpendicular to V.P. A section plane cuts the axis of the pyramid at a height of 45 mm from the base and at angle of 15º with the horizontal. Draw the development of the truncated pyramid

126 A b’a’ c’f’ d’e’ o’ d1 45 d2 120 d1 d3 O d3 F 126 d1 d2 d3 M d2 P E 15º J d1 X Y D a b c d e f o C 40 40 B A