Enquiry skills: error and results 1) The Bungee Jump Company tested the strength of a number of different bungee cords. Each. cord
was tested with a 75 kg test mass (to represent a bungee jumper), which was dropped from a 60 m
bridge over a river valley. All of the cords used were 20 m long.
Here are the results:
Extension (m)
Mean extension (m)
Thickness of cord
(mm)
30
60
90
120
150
Repeat 1
30
16
11
7
6
Repeat 2
32
14
10
8
7
Repeat 3
32
18
9
6
5
a) Calculate the mean extension for each thickness of cord and fill in the table.
b) Give 3 reasons why the company repeated the test 3 times:
i.
ii.
iii.
c) Explain how these results could be tested for reproducibility
2) Student A carried out a similar investigation in her classroom. They didn't have access to all the
same equipment as the Bungee Jump Company in question 1.

answer: ratio of volume of cone (with 3 times the height and equal diameter) to volume of cylinder is 2 to 1. the value of π is not used.

step-by-step explanation:

radius is diameter/2 = 4.

area of circle is π r^2.

volume of cylinder is height × area of base = hπr^2 = 3(4^2) π = 48π cubic inches.

not knowing the formula for volume of cone, i calculate it using calculus (which is for calculating things).

volume of cone is integral 0 to h area(y) dy. area(y) is π r(y)^2. r(y) runs r to zero as y runs zero to h, r(0) = r, r(h) = 0.

r(y) = r - r/h y

area(y) = π (r - r/h y)^2 = π (r^2 - 2r^2y/h + r^2y^2/h^2) = π r^2(1-2y/h+y^2/h^2)

antiderivative area(y) = π r^2 (y-y^2/h+y^3/(3h^2))

integral 0 to h = π r^2(h-h^2/h+h^3/(3h^2) - (0)) = π r^2(h - h + h/3) = π r^2(h/3) = π/3 r^2 h

volume of this cone is π/3(4^2)18 cubic inches.

= 6 16 π = 96π cubic inches.

cone has twice the volume, 96/48.

cone height is 6 times the cylinder.

ratio of volume formula: π r^2 cancels.

cone over cylinder ratio is 6h/3 to h, 2 to 1.

hope this is what you were asking for!

step-by-step explanation:

the answer is $42.96

step-by-step explanation: