Technology Grade 9 June Common 2010 Memo (English)

Province of the EASTERN CAPE EDUCATION SENIOR PHASE GRADE 9 JUNE 2010 TECHNOLOGY MARKING GUIDELINE MARKS: 100 TIME: 2 hours This marking guideline consists of 7 pages.

2 TECHNOLOGY MARKING GUIDELINE (JUNE 2010)

(JUNE 2010) TECHNOLOGY MARKING GUIDELINE 3 SECTION A: STRUCTURES QUESTION 1 1.1 A 3 √ B 10 √ C 1 √ D 7 √ E 6 √ F 9 √ G 5 √ H 4 √ I 2 √ J 8 √ (10) 1.2 1.2.1 Corrosion is the slow process of material being eaten away. √ 1.2.2 galvanised iron √ (2) [12] QUESTION 2 2.1 2.1.1 To build a bridge across the deep canyon √ (1) 2.1.2 (a)  For people, vehicles, animals, etc to cross the canyon.  To get building material from the nearest town to the village.  to get the raw material from the mine to the nearest processing plant. (any two of the above) √√ (2) (b) The canyon is too deep for a bridge to rest on pillars. √√ (2) (c) No √ In this case the bridge should rather be functional and fulfill its purpose properly. √ (2) (d)  rails for pedestrians  strength for heavy loaded trucks from the mine (any other acceptable answers) √√ (2) (e)  labour  material e.g. cement  transport (any other acceptable answers) √√ (2) 2.2 Learner’s choice Please take not that there must be no pillars reaching the bottom of the canyon. (1)

4 TECHNOLOGY MARKING GUIDELINE (JUNE 2010) Possible answer: Arch bridge √ 2.3 √√ basic arch shape √ neatness and clearness of sketch (any of the above types of Arch bridges or structures of similar design) Reason: All the other types of bridges have pillars that would have to go down to the bottom of the canyon. √ This canyon is too deep for the use of pillars. √ (5) 2.4 Suspension bridge: Two very thick, long main cables, anchored at each end that stretch the full length of the bridge. √ Only the two main cables are supported by the towers. √ Cable-stayed bridge: One type of cable which directly supports the deck and is much shorter than the main cables of a suspension bridge. √ All cables are fixed to a tower at one end and to the deck at the other end. √ (4) [21] QUESTION 3 3.1 3.1.1 E: Compressive √ F: Tensile √ (2) 3.1.2 A flexible √ D stiff √ B stiff √ E stiff √ C flexible √ F flexible √ (6) [8]

(JUNE 2010) TECHNOLOGY MARKING GUIDELINE 5 QUESTION 4 4.1 4.1.1 static force √ 4.1.2 dynamic force √ 4.1.3 dynamic force √ (3) 4.2 4.2.1 Even loads: the mass of the load on each side is exactly the same. √ Uneven loads: there are loads of different weights on each side of the structure. √ (2) 4.2.2 Even loads √√ Uneven loads √√ (The diagrams above illustrate the difference between even and uneven loads. Any other illustrations can be accepted as long as it can differentiate between the two loads) (4) [9] TOTAL SECTION A: 50

6 TECHNOLOGY MARKING GUIDELINE (JUNE 2010) SECTION B: SYSTEMS AND CONTROL (Mechanical) QUESTION 1 1.1 Object Input Output person turns the the load is lifted fairly easily hand-driven pulley handle on the winch winch √ √ person uses a the jack lifts the car crank to turn the car jack handle √ √ person’s hand the scissors cut the paper applying force to scissors the scissors √ √ person’s hand the mixers of the whisk spin applies force to to whisk turn the handle √ √ person pushes on the wheels turn / the bicycle bicycle’s gear the pedal moves system √ √ [10] QUESTION 2 2.1 2.1.1 A gear is a wheel with cogs that mesh with another gear. √ (1) 2.1.2 The driver gear starts the movement of the gear system. √ The driven gear moves because the driver gear forces it to move. √ (2) 2.1.3 When the two gears are meshed and turning, the driver gear will for example turn clockwise. √ This forces the driven gear to turn in the opposite direction. √ (2) 2.1.4 driver gear label = √ driven gear label = √ direction of driver gear = √ direction of driver gear = √ (4)

(JUNE 2010) TECHNOLOGY MARKING GUIDELINE 7 2.2 Product Gear How input changed to output mechanism shifting rack-and- a worm supplies a rotary movement for the jaws spanner worm gear to move in linear movement. √ √ hand drill bevel gear rotary movement around the axis at handle causes a rotary movement of the bit. √ √ corkscrew rack-and-spur handle at top turns in a rotary movement forcing gear the arms to move up and down (oscillating movement) or the screw moves up and down (linear movement) √ √ (6) 2.3 2.3.1 Learners must first find the revolutions per minute at B 120 A = 3 30 revolutions x 3 = 90 r.p.m. 40 B √ √ √ √ √ (C is fixed to B and therefore rotates at the same speed, i.e. 90 revolutions per minute) Learners now find the revolutions per minute at D 80 C 90 revolutions (at C) x 4 = 360 r.p.m. = 4 20 D √ at D √ √ √ √ (10) 2.3.2 D revolves in a clockwise direction √ (1) [26] QUESTION 3 3.1 ratchet and pawl mechanism (1) 3.2 ratchet √ OR pawl √ neatness of sketch - √ (3) [4]

8 TECHNOLOGY MARKING GUIDELINE (JUNE 2010) QUESTION 4 4.1 Velocity ratio can be defined as the ratio of the distance moved by the effort to the distance moved by the load. √ (1) 4.2 4.2.1 Load 4 Mechanical advantage = = = 4 Effort 1 √ √ √ (3) 4.2.2 Load 100N Effort = = = 25N Mechanical advantage 4 √ √ √ (3) 4.2.3 The distance moved by effort: Distance moved by effort 4m = = 1m Velocity ratio 4 √ √ √ (3) [10] TOTAL SECTION B: 50 GRAND TOTAL: 100