Chronology Current Month Current Thread Current Date
[Year List] [Month List (current year)] [Date Index] [Thread Index] [Thread Prev] [Thread Next] [Date Prev] [Date Next]

Re: [Phys-l] three central misconceptions about relativity



Gday All,

John Denker earlier stated <Again: Just because Einstein used contracted rulers and dilated
clocks in 1905 doesn't mean it is a good idea. In fact it is a terrible idea. It is *incompatible* with a modern (post-1908) understanding of the subject.>

In our state mandated Physics Syllabus, the document we base our teaching on and on which our state wide assessment material is based it says (in part)

1. identify that if c is constant then space and time become relative

2. discuss the concept that length standards are defined in terms of time in contrast to the original metre standard

3. explain qualitatively and quantitatively the consequence of special relativity in relation to:

– the relativity of simultaneity – the equivalence between mass and energy – length contraction – time dilation – mass dilation



Remembering that student are going to be asked question directly on this material, what is the *best* approach for giving my students a good intro level understanding of relativity while at the same time enabling them to answer questions in the state test?



They are asked questions such as



a) How has our understanding of time been influenced by the discovery of the constancy of the speed of light?

b) piece of radioactive material of mass 2.5 kilogram undergoes radioactive decay. How much energy is released if 10 grams of this mass are converted to energy during the decay process?

c) A mass is moving in an inertial frame of reference at a velocity v relative to a stationary observer. The observer measures an apparent mass increase of 0.37%.Calculate the value of v in m/s.


Regards

Peter Craft
Head Teacher Science
Corowa High School

Phone 02 6033 1889
Fax 02 6033 1889
________________________________________
**********************************************************************
This message is intended for the addressee named and may contain
privileged information or confidential information or both. If you
are not the intended recipient please delete it and notify the sender.
**********************************************************************