W1-2-60-1-6
JOMO KENYATTA UNIVERSITY OF AGRICULTURE AND TECHNOLOGY
University Examinations 2018/2019
YEAR IV EXAMINATION FOR THE DEGREE OF BACHELOR OF ARCHITECTURAL STUDIES

ABA 2403:  BUILDING ENVIRONMENTAL SCIENCE II (ACOUSTICS)

DATE:   DECEMBER, 2018				        		 TIME:  2 HOURS

INSTRUCTIONS:  	 Answer Question ONE and Any Other TWO Questions.

Question One (30 Marks)

a)	Describe the following terms in relation to sound.

i.	Decibel scale		[4 marks]
ii.	Wave length 		[4 marks]

b)	Explain what happens to a sound wave when it is incident on a surface.	[3 marks]

c)	Distinguish between the terms ‘noise and sound’.	[6 marks]

d)	Discuss the main sound absorption mechanisms.	[6 marks]

Question Two (20 Marks)

a)	Define the following terms.	

i.	Sound transmission coefficient 		[4 marks]
ii.	Sound transmission class			[4 marks]

b)	Describe the main categories of factors affecting outdoor sound propagation.		[12 marks]

Question Three (20 Marks)

a)	Explain how sound is comparatively transmitted in solids, liquids and gases.		[6 marks]

b)	Discuss seven factors that affect how sound is absorbed in porous materials.		[14 marks]

Question Four (20 Marks)

a)	Explain how sound transmission happens through opening, highlighting the key 	mechanisms that contribute to such.	[6 marks]

b)	You have been appointed to design a recording studio in the context of a noisy urban 	environment. Outline the key design considerations that you will  make to develop a 	solution that functions optimally from an acoustics perspective.	[14 marks]