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VCE Stuff => VCE Mathematics => VCE Mathematics/Science/Technology => VCE Subjects + Help => VCE General & Further Mathematics => Topic started by: zibb3r on August 16, 2011, 04:46:20 pm

Title: Do you know the answer?????
Post by: zibb3r on August 16, 2011, 04:46:20 pm
1) The cross sectional area of a metal beam used in skyscraper production is 153 cm2 and the length of the beam is 3m.  What volume of metal is required to produce the beam???

a)459cm3
b)4590cm3
c)45900cm3
d)459m3
e)45900m3


2 and 3) A cylindrical drum has the following properties:
-a thickness of 2cm
-a total diameter of 52cm (including the 2cm thickness)
-a height of 27cm

Find the surface area of the outside curved surface:

a)324cm2
b)509cm2
c)1018cm2
d)3053cm2
e)12215cm2

Calculate the volume that could fill the inside of the drum:

a)1357cm3
b)2120cm3
c)3054cm3
d)5429cm3
e)8482cm3



Thanksyou so much!!!!!!!!!!
Title: Re: Do you know the answer?????
Post by: paulsterio on August 16, 2011, 05:17:01 pm
1) - Volume = C/S Area x Length = 153cm x 3m = 153cm x 300cm = 45900cm3 = C

2) - TSA Of a Cylinder = 2(pi)(r)(h+r) = 2 x 3.14159 x (52/2) x (27 + 52/2) = 8654cm2 (which isnt there - can someone shed some light on this)?
Title: Re: Do you know the answer?????
Post by: REBORN on August 16, 2011, 05:51:38 pm
It says the outside curved surface...not the whole TSA?
Title: Re: Do you know the answer?????
Post by: paulsterio on August 17, 2011, 01:04:52 am
Quote from: ssNake on August 16, 2011, 05:51:38 pm
It says the outside curved surface...not the whole TSA?

Good point, in that case

A = 2(pi)(r)(h) will give the answer

A = 2 x 3.14159 x 52/2 x 27
Title: Re: Do you know the answer?????
Post by: Kiro Kompiro on August 30, 2011, 01:04:35 pm
Quote from: paulsterio on August 17, 2011, 01:04:52 am
Quote from: ssNake on August 16, 2011, 05:51:38 pm
It says the outside curved surface...not the whole TSA?

Good point, in that case

A = 2(pi)(r)(h) will give the answer

A = 2 x 3.14159 x 52/2 x 27

=4410.8 cm squared which is not there?
Title: Re: Do you know the answer?????
Post by: Kiro Kompiro on August 30, 2011, 01:08:18 pm
volume that will fill is the volume of the inner cylinder,  diameter is 52-2=50, radius is 25 cm

volume = pi*r*r*h
=3.14159*25*25*27
=53014 cm cubed which is not an answer?