Olivia Benny Plant fibre strength CPAC
Aim: To investigate the properties (strength) of different plant fibres from plant as well as developing practical skills
Variables:
Independent variables The independent variable in this experiment is the different
plants that the fibres are being extracted from e.g New Zealand
flax and celery, this is important for the investigation to compare
which plants fibres withstand more weight before breakage.
Another independent variable is the mass added onto the plant
fibres to measure the amount of mass the fibre can withstand
before breakage
Dependant variable The dependant variable is the variable being measured and that’s
the amount of mass a plant fibre can withstand before breakage
and also occupy results in order to calculate the tensile strength
of a fibre.
Control variables Control variables include:
- keeping the length and the width of the fibre being extracted
from the plant, as the wider a fibre is the less tensile strength it
may have, the length and width can affect the tensile strength
and the mass it can withstand, to control this I measured the
length of the fibre each time with a ruler
-Another control variable is keeping the amount of time the
masses are kept onto the plant fibre the same as that can affect
the overall strength a fibre has e.g., keeping the weight on for 20
seconds each
-Another control variable is the intervals at which the masses are
added on e.g. in this experiment the weights were added on 50g
at a time, as different intervals and not keeping it constant can
have overall effect on the results obtained
-Another control variable is the species/origin/age of the plant
which the fibres are extracted from, since these factors can have
effect onto the overall tensile strength, as well as the growing
conditions and environment the plant thrives in and is extracted
from
Apparatus:
Apparatus Why is it used?
Clamp The clamp is used to hold the bulldogs tightly as well as position
the two clamps away from each other at a distance which is the
same length of the plant fibre, this is also to ensure accurate
results can be taken as the same distance between the clamps
must be controlled as distance can be a factor which can affect
the results
Ruler The ruler is used to measure the length of the fibres extracted to
ensure they are the same length; this is to ensure the practical is
accurate and this variable is controlled. The results can differ if
the length is not controlled, the same can be applied with the
length, in the experiment.
Weights The weights are used to add mass onto the plant fibre to measure
how strong the plant fibre is, the mass used was in intervals of
50g, the results obtained can be implemented to calculate the
plant fibres overall tensile strength
Celery/ New Zealand flax The celery and New Zealand flax are very important as this is
what is being measured, the plant fibres come from these plants
and it is used as a comparison with each other, each fibre from
each plant is used in the experiment to calculate the overall plant
tensile strength then overall devise a conclusion about the two
Bulldog clips The bulldog clips are used to hold either ends of the fibre securely
to ensure that is does not slip away when adding mass onto the
plant fibres, they also ensure the fibre is held in a straight
position so the results obtained are as valid as possible
White tile & scalpel/forceps The while tile and scalpel are used together, the while tile is used
to place the specimen (either the New Zealand flax or the celery)
and the scalpel and forceps are used to help extract a thin piece
of fibre from both the plants, this requires careful precision and
Aim: To investigate the properties (strength) of different plant fibres from plant as well as developing practical skills
Variables:
Independent variables The independent variable in this experiment is the different
plants that the fibres are being extracted from e.g New Zealand
flax and celery, this is important for the investigation to compare
which plants fibres withstand more weight before breakage.
Another independent variable is the mass added onto the plant
fibres to measure the amount of mass the fibre can withstand
before breakage
Dependant variable The dependant variable is the variable being measured and that’s
the amount of mass a plant fibre can withstand before breakage
and also occupy results in order to calculate the tensile strength
of a fibre.
Control variables Control variables include:
- keeping the length and the width of the fibre being extracted
from the plant, as the wider a fibre is the less tensile strength it
may have, the length and width can affect the tensile strength
and the mass it can withstand, to control this I measured the
length of the fibre each time with a ruler
-Another control variable is keeping the amount of time the
masses are kept onto the plant fibre the same as that can affect
the overall strength a fibre has e.g., keeping the weight on for 20
seconds each
-Another control variable is the intervals at which the masses are
added on e.g. in this experiment the weights were added on 50g
at a time, as different intervals and not keeping it constant can
have overall effect on the results obtained
-Another control variable is the species/origin/age of the plant
which the fibres are extracted from, since these factors can have
effect onto the overall tensile strength, as well as the growing
conditions and environment the plant thrives in and is extracted
from
Apparatus:
Apparatus Why is it used?
Clamp The clamp is used to hold the bulldogs tightly as well as position
the two clamps away from each other at a distance which is the
same length of the plant fibre, this is also to ensure accurate
results can be taken as the same distance between the clamps
must be controlled as distance can be a factor which can affect
the results
Ruler The ruler is used to measure the length of the fibres extracted to
ensure they are the same length; this is to ensure the practical is
accurate and this variable is controlled. The results can differ if
the length is not controlled, the same can be applied with the
length, in the experiment.
Weights The weights are used to add mass onto the plant fibre to measure
how strong the plant fibre is, the mass used was in intervals of
50g, the results obtained can be implemented to calculate the
plant fibres overall tensile strength
Celery/ New Zealand flax The celery and New Zealand flax are very important as this is
what is being measured, the plant fibres come from these plants
and it is used as a comparison with each other, each fibre from
each plant is used in the experiment to calculate the overall plant
tensile strength then overall devise a conclusion about the two
Bulldog clips The bulldog clips are used to hold either ends of the fibre securely
to ensure that is does not slip away when adding mass onto the
plant fibres, they also ensure the fibre is held in a straight
position so the results obtained are as valid as possible
White tile & scalpel/forceps The while tile and scalpel are used together, the while tile is used
to place the specimen (either the New Zealand flax or the celery)
and the scalpel and forceps are used to help extract a thin piece
of fibre from both the plants, this requires careful precision and
