Westwood D&T 2024 4E5N(7059) Prelim Marking Scheme

Page 1 of 6 Setter: Ahmad Luqman Mark Scheme 4E5N Prelim QP1 2024 Qn s Answer and marking description Marks 1a Design and make a portable lamp [0.5] to be placed on the table beside the BBQ pit [0.5] for BBQ-pit users [0.5] to check / see if their food is fully cooked [0.5] 2 1b Observe BBQ-pit users [1] and document [1] their actions, habits, difficulties etc [1] (or) Observe environment around BBQ-pit [1] to find out surrounding conditions [1] with documentation (record down) [1] 3 1c Sustainability is crucial for designers because it ensures that products are… environmentally friendly / reduce waste / conserve resources / minimizes environmental impact of manufacturing / minimizes environmental impact of disposal/ promotes long-term durability / and efficiency / economically viable/ influence users to be socially responsible. Any two points from the above or any other suitable answers 2 1d - the product should be made of fire-resistant material [1] so that it can withstand prolonged exposure to heat [1]. - the product should be lightweight [1] so that it is convenient for transportation [1]. 2 1e Clarity and Proportion [2] Feasibility [1] Interesting design (shape) [1] Light can illuminate large area of BBQ pit [1] Portability [1]

Page 2 of 6 1f Clarity and Proportion [3] Protect hand from heat [1] 4 1g Sketch of anthropometric hand part [1] Related anthropometric dimensions use [1] linked to parts of the design [1] 3 1h The study of the design of products so that people/user can interact [1] with them in a comfortable, safe and efficient way [ any 2 x ½ ] 2 1i Analyse product prototype against (Need / Brief) [ ½ ] / Specifications [1] to confirm if prototype works accordingly / check for improvements [1] (or) any evaluation methods eg. PMI, SWOT etc, with some explanation. 2 2a Shell structure 1 2b Contain [1] – The wooden wardrobe contains / holds the clothings inside [1] to be at 1 location. Protect [1] – The wooden wardrobe protects the clothings from dust / direct light shine [1] 4 2ci Bending 1 2cii Simply Supported [1] beam 1 2ciii 3

Page 3 of 6 2civ Sheet materials made stronger [1] by joining/gluing several pieces together [1] 2 2cv Any suitable cross section [1] clarity of sketch [1] 2 2cvi Appropriate reinforcement [ 0, 1, 2 ] - e.g. braces, gusset plates, webbing etc · Correct name [0, 1] · Clarity [1] 4 3ai 2nd Class lever 1 3aii Load (L) is in middle [ 1 ] Fulcrum and Effort indicated [1] Direction of forces [ ½ ] x2 3 3aiii Ball bearing for Speed/smooth rotation [1], so that wheelbarrow can move easily [1] 2

Page 4 of 6 (or) Any suitable explanation with reason. 3bi Mechanism A : Chain Mechanism B: Sprocket 2 3bii Rotary [1] (input - pedalling) to Linear [1] (output – bicycle move forward) 2 3biii Bicycle needs to move heavy load (user + internal weight) [1] , but the (Flat) belt in Fig. 3.3 will slip (pulley rotate, belt no move) under heavy load [1] ** Belt will slip off the pulley easily [1] (or) Any suitable explanation with reason. 2 3biv 2D or 3D Sketch clarity [1] Any viable belt that increases grip/surface area contact [1] 2 3ci 3 3cii The output/back wheel is attached to a bigger/more teeth gear [1] than the input gear to achieve a slower rotation speed (or) Any suitable explanation with reason. 1 4a Sensing Circuit CONNECTION Cannot make out connection [0] / Partial Correct [1] / Fully Correct [2] 6

Page 5 of 6 * Above [ ] refer: give the respective [ ½ ] for correct components’ names ; except Potentiometer/Variable resistor is [1] 4bi Closed Loop Control System [1] 1 4bii Corresponding to answer in 4b)i. [1] (i.e. if answer “Open-Loop” in above, then the diagram should be “Open-Loop” * 3 / 4 stages all correct [1] 2 4c Single-use batteries disposed after the current runs out [1] may cause pollution to environment [1] / need new raw resources to make new ones [1] (deplete natural resources) / rechargeable batteries more sustainable [1], etc (or) Any suitable explanation with reason. 2 4di 555 [1] (timer IC chip) 1 4dii 4026 is used to drive / make the 7-segment LED [ ½ ] to display numeric digits (numbers) [ 1 ] in ascending order [ ½ ]. 2 4e 3 x LEDs [1] ; connected in parallel [1] Switch is SLIDE SWITCH [1] 4

Page 6 of 6 battery indicated as 9V [1] ** If draw circuit symbol instead of physical component, can [ ½ ] each if is correct ** END OF PAPER