Page 150 - CAPE Green Engineering Syllabus 2016.docx_Neat

-3- 02265020/CAPE/KMS 2015 SPEC

GREEN ENGINEERING
UNIT 2 - PAPER 02
KEY AND MARK SCHEME

Question 1. (continued)

S.O Suggested Response Mark Marks
Allocation KC AK PA

2:1:2 (d) 4 4

 1 mark each for calculating L/K = R for
lightweight concrete blocks and brick

 1 mark for calculating total resistivity
(Rtot)

 2 marks for calculating U=1/(Rtot)

2:1:3 (e) 4 4

Role

 Cavity is filled with air which acts as an
insulator

 Cavity as part of material reduces weight
density ratio

 Cavity can be used as communication
channels ( for example, cables for
telecommunication)
(2 marks for minimum 2)

Deficiencies

 Can transfer heat by convection
 Can create air leakage
 Can result in condensation if not

properly sealed
(2 marks for minimum 2)

TOTAL 20 MARKS 12 8 0