Course:PHYS341/2019/pre-reading/Q9

Self-study for Quiz 9 on March 25th.

1 The fundamental frequency of a sung note depends on:

	(a) the mass of the vocal folds.
	(b) the tension of the vocal folds
	(c) the length of the vocal tract.
	(d) the shape of the vocal tract.
	(e) whether the singer's mouth is wide open or not.
	(f) whether the singer's nasal passage is open or not.

2 A tall heavily-built man sings the same note as a much shorter, slightly-built woman. Even if they sing a note at the same pitch, the two voices still sound radically different, primarily because of:

	(a) the masses of their vocal folds.
	(b) the tensions of their vocal folds
	(c) the lengths of their vocal tracts.
	(d) the shape of their vocal tract.

3 The bell of a brass instrument behaves as

	(a) a closed pipe for lower frequencies.
	(b) a closed pipe for higher frequencies.
	(c) an open pipe for lower frequencies.
	(d) an open pipe for higher frequencies.
	(e) an infinitely long pipe for lower frequencies.
	(f) an infinitely long pipe for higher frequencies.

4 and thus:

	(i) suppresses standing waves in the pipe of higher frequencies.
	(ii) suppresses standing waves in the pipe of lower frequencies.

5 A bass drummer aims to excite the (0,1) mode of the drum membrane. A timpanist aims to excite the (1,1) mode of the drum membrane. Where on the drum should each player strike the instrument? (See http://hyperphysics.phy-astr.gsu.edu/hbase/Music/cirmem.html).

	(a) Edge (bass drum), centre (timpani)
	(b) Edge (bass drum), edge (timpani)
	(c) Centre (bass drum), edge (timpani)
	(d) Centre (bass drum), between the centre and the edge (timpani)
	(e) Between the centre and the edge (bass drum), centre (timpani)
	(f) Between the centre and the edge (bass drum), between the centre and the edge (timpani)