Physics 7. Homework # 5
Due:
5/3
1) What was the motivation for
hypothesizing the existence of the ether?
a) The idea that motion cannot
occur in a vacuum
b) The belief that light needs a
medium to propage in, like any other wave
c) That it simplifies Maxwell’s
equations
d) That is required by
2) What
is one difference between microwaves and X-rays?
a) They are both electromagnetic waves
distinguished only by their wavelength, which is much smaller for X-rays
b) Their very nature: X-rays are
produced by magnets and not by moving charges while microwaves require electricity
and no magnets.
c) Microwaves are electromagnetic
radiation, X-rays are bits of atoms produced in atomic reactions
d) Microwaves affect organic
tissue but all life is completely immune to X-rays
3) Why is the Lorentz
contraction idea an unsatisfactory hypothesis?
a) Because it was proven wrong
b) Because it contradicted
c) Because it contradicted
Maxwell’s equations
d) Because it had no goal or
consequence other than hiding the ether from observation: it was unfalsifiable
4) When you drop a stone in a pond a
wave spreads form the point where the stone was dropped. On the other hand, if
you look at the leaves floating on the pond,
a) They move away being carried
by the wave
b) They are attracted to the
point where you dropped the stone
c) They stay in place bobbing up
and down: the wave spreads carrying energy, but does not carry water or leaves with
it.
d) They immediately sink