Physics-practical-work.ppt practical in physics

Physics is the natural science of matter, involving the study of matter, its fundamental constituents, its motion and behavior through space and time, and the related entities of energy and force.[1] Physics is one of the most fundamental scientific disciplines.[2][3][4] A scientist who specializes in the field of physics is called a physicist.

Physics is one of the oldest academic disciplines and, through its inclusion of astronomy, perhaps the oldest.[5] Over much of the past two millennia, physics, chemistry, biology, and certain branches of mathematics were a part of natural philosophy, but during the Scientific Revolution in the 17th century, these natural sciences branched into separate research endeavors.[a] Physics intersects with many interdisciplinary areas of research, such as biophysics and quantum chemistry, and the boundaries of physics are not rigidly defined. New ideas in physics often explain the fundamental mechanisms studied by other sciences[2] and suggest new avenues of research in these and other academic disciplines such as mathematics and philosophy.

Advances in physics often enable new technologies. For example, advances in the understanding of electromagnetism, solid-state physics, and nuclear physics led directly to the development of new products that have dramatically transformed modern-day society, such as television, computers, domestic appliances, and nuclear weapons;[2] advances in thermodynamics led to the development of industrialization; and advances in mechanics inspired the development of calculus.
Natural philosophy
Main article: Natural philosophy
Natural philosophy has its origins in Greece during the Archaic period (650 BCE – 480 BCE), when pre-Socratic philosophers like Thales rejected non-naturalistic explanations for natural phenomena and proclaimed that every event had a natural cause.[13] They proposed ideas verified by reason and observation, and many of their hypotheses proved successful in experiment;[14] for example, atomism was found to be correct approximately 2000 years after it was proposed by Leucippus and his pupil Democritus.[15]

Aristotle and Hellenistic Physics
During the classical period in Greece (6th, 5th and 4th centuries BCE) and in Hellenistic times, natural philosophy developed along many lines of inquiry. Aristotle (Greek: Ἀριστοτέλης, Aristotélēs) (384–322 BCE), a student of Plato, wrote on many subjects, including a substantial treatise on "Physics" – in the 4th century BC. Aristotelian physics was influential for about two millennia. His approach mixed some limited observation with logical deductive arguments, but did not rely on experimental verification of deduced statements. Aristotle's foundational work in Physics, though very imperfect, formed a framework against which later thinkers further developed the field. His approach is entirely superseded today.

He explained ideas such as motion (and gravity) with the theory of four elements. Aristotle believed that each of..

1. Physics
investigations

2. Learning outcomes
analyse roles and effectiveness of practical activities in science
consider how to mitigate the damaging effect of assessed practicals
discuss the design and evaluation of standard experiments suitable for
GCSE students
develop a repertoire of physics questions suitable for open-ended
investigations
discuss collecting and recording data, ways of improving the quality of
data
master a variety of simple measurement techniques used in physics
use a straight line graph through the origin as a test for direct
proportionality

3. Defining ‘practical work’
‘Any teaching and learning activity which involves, at
some point, the pupils in observing or manipulating real
objects and materials.’

4. Practical work
Very diverse in nature and purpose
Primary learning objectives:
•developing knowledge and understanding of the natural world
•practical capability - using scientific equipment or following
standard procedures
•developing understanding of a scientific approach to enquiry

5. Scientific enquiry
The quality of evidence is always of concern.
When planning and carrying out practical investigations,
pupils need to ask, for example,
•Is my method valid?
•Can I rely on my data when drawing a conclusion?
•Are uncertainties in the measurements small enough?
•Does the difference between one measurement and another
reflect a real change in the thing being measured?

6. NASA Astronomy
Picture of the Day
February 7, 1998
COBE was launched in November 1989. By March 1991, the research team saw
this pattern emerge in their data, but they could not be sure what was noise and
what was real. Possible sources of systematic error were rigorously identified,
checked and cross-checked. Only in April 1992 were the team ready to go public.

7. Instruments used in physics
•micrometer screw gauge – readings on sleeve (0.5 mm
graduations) & thimble (2 x 50): reads to 0.01 mm
•callipers – vernier scale divides 1 mm by 10: reads to 0.1 mm
VPL’s two simulations can be used for practice.
other instruments with
vernier scales
–travelling microscope
–spectrometer

8. Now try this
In pairs:
1 Use a micrometer to measure the diameter or
thickness of various objects.
2 Use vernier callipers to measure a variety of lengths.

9. Another learning objective
Communication skills
Pupils need to learn how to:
•analyse and present data;
•draw conclusions from data;
•evaluate the quality of data;
•present an account of a practical task.

10. Now try this
In groups of three:
Investigate the relationship between the distance a ‘hot
wheels’ toy car is drawn back and how far it then
travels forward.
Record and analyse any data that you collect.

11. ‘The language of measurement’
Booklet from Nuffield-ASE
Aims:
to achieve a common understanding of important terms that arise
from practical work in secondary science e.g. ‘accuracy’ and
‘precision’
as used by professional scientists (agreed among international
metrology institutes - in the UK, National Physical Laboratory,
LGC)
Target audience: teachers, ITE and CPD providers, publishers,
awarding bodies.

12. Straight line graphs tell a story
R
V
VI
kxyxy


constant e.g.
or
alityproportiondirect
re temperatu pressure gas e.g.
intercept gradient, where
iprelationshlinear
v
ycmcmxy 

13. Straight line graphs tell a story
ll
g
T
g
l
T


constant
4
2 check that Replot to
2
2

periodic time, T, for a pendulum, length l

14. Boyles’ law
Equation:
Graph: Plot p against 1/V (dependent against independent variable)
Straight line, passing through the origin with gradient = nRT
V
nRT
p
nRTpV



15. Equation:
Q is found by using energy = power x time
energy = current x voltage x time
Equation:
Graph: Plot temperature change ∆T against time t
Straight line, passing through the origin with gradient
So
Specific heat capacity
TmcQ 
mc
IV

gradientm
IV
c



16. Now try this
In pairs:
What graph you would need to plot to confirm the
following relationships?
1 Seafloor spreading hypothesis: separation distance of
magnetic stripes, x, increases with age of seafloor, t.
2 Intensity of a light source:
I = intensity, x = detector distance from source, k = constant
2
x
k
I

17. Another set of learning objectives
Personal development
Practical work can help pupils to:
•become more motivated to study science
•become more confident and self-reliant
•learn something about working effectively with
others

19. More effective practical work
Characteristics:
•the task has a limited number of intended learning
outcomes
•the task design highlights the main objectives and
keeps ‘noise’ to the minimum

20. Two worlds
domain of real
objects and
observable
things
domain of ideas

21. More effective practical work (2)
•Stimulate the pupils’ thinking beforehand, so that
the practical task answers a question which the
pupil is already thinking about.
•If the task requires the pupils to make links
between the domain of objects and observables
and the domain of ideas, ensure that the structure
of the task ‘scaffolds’ their thinking.

22. Open-ended investigations
In pairs:
Discuss experiments listed on the handout ‘Ideas for
investigations at KS4’. Which of them might work with
your pupils? what year/class?
There is also a different list for A-level Physics.

23. Teaching challenges
Various factors constrain opportunities for student investigations.
•assessment requirements from some awarding bodies. e.g.
affects what teachers value; students can be tempted to copy
what others are doing, even when it is ill-advised.
•apparatus & technician support available can limit the variety of
approaches to investigating a similar question.
Conclusion: It may be best to encourage lots of simple, open-
ended investigative work at KS3, with the aim of developing
practical skills and encouraging scientific thinking – not
assessment.

24. Further reading
Breithaupt opening chapter ‘Units and measurements’
Robin Millar (2010) Analysing Practical Science Activities
to assess and improve their effectiveness. ASE
Peter Campbell (ed.) (2010) The language of measurement:
terminology used in school science investigations.
ASE
extracts of both ASE booklets: www.gettingpractical.org.uk/Books.php