Identify two situations where CONVEX mirrors are used
and explain why.
Why is the curved bathroom mirror considered a
magnifying mirror. Explain the optics.
Why are telescopes made with parabolic mirrors instead
of spherical mirrors?
Why is a multi-trillion dollar industry dependent on a
small critical angle of plastic?( Hint fiber optics).
An improvement in production technology will cause the
production-possibilities curve to
become less curved
become more curved
shift outward
shift inward
3. According to the concept of scarcity in economics
wants will be fully satisfied sometime in the future
there are no free goods
free goods and scarce goods are the same
the wants of society cannot be satisfied by the goods and
services that can be produced from given resources
4. The production-possibilities curve shows
All of the above...
explain the idea of blackbody radiation, include a discussion of
the following topics:
• Why
is Planck’s law of radiation important in the history of physics?
What are Wien’s law and the Stefan-Boltzmann law, and how are they
related to Planck’s law?
• How
are these laws applied in astrophysics and other areas of science?
Give some examples.
(a) Explain the features of the spectra of alpha, beta and gamma
radiation.
(b) Why does alpha/beta spectroscopy have to be conducted in an
environment different from that for gamma spectroscopy?
- Comparer a typical CT radiation dose to that of a
planar x-ray and explain why there is a difference?
The question is asking for a comparison between CT
radiation and X-ray ( planner) !!
In tropical regions less energy is emitted by the earth as
infrared radiation than is absorbed as solar radiation averaged
over the year. Explain briefly why tropical regions do not
continually get warmer year after year after year.
Consider the blackbody radiation emitted at a temperature
of
500◦C.
(i) Explain why a tungsten wire in an old-fashioned light-bulb
starts
to glow as it becomes sufficiently hot.
(ii) Calculate the percentage pressure increase of the
blackbody
radiation if the temperature is raised to 550◦C.
An electron escapes the hot tungsten wire and is
subsequently
trapped in a one-dimensional square quantum well. The
potential
outside the well can be approximated as infinite.
(iii) Sketch the probability distribution of the electron...
Explain why the stiffness of a discontinuous fiber composite is
less than that of a continuous fiber composite with the same
constituents and same proportion of reinforcement.