Kind: captions
Language: en
[Applause]
you know what's been popular Rod what's
that our Slinky Drop video that is
popular isn't it yeah do you want to do
another Slinky drop that's not a slinky
this is a
slinky that is a that is an excellent
Slinky we should drop that one we want
to see whether a long Slinky and where F
A MERS up here whether a long Slinky
works the same as a short Slinky because
some people on YouTube don't really
believe that it's going to work the same
or or they want to see it we're about to
find out all right I'll go film it from
the grass and you drop the slinky fine
okay
[Music]
here you go Rod did you see it yeah that
was a good drop did you get it I don't
know I think so we got to check the
cameras well I think it it tended to
Tumble us it got got right down to the
bottom and I think it's going too fast
and tumbling I think you better we
better do that one again we got to do it
again
yeah all
right
[Music]
[Applause]
oh thanks Derek oh not a problem I saw
that it still tumbles when it gets to
the end yeah it's clear to me that you
wouldn't want to be sitting at the end
of this under an airplane no definitely
not no much better to actually have a
parachute exactly so what do you think
about the explanations that have been
going around on the web you know people
talking about the center of mass is
falling with the acceleration due to
gravity 9.8 m/s squared is that true uh
yes it is and then the bottom end people
are saying it's actually shooting up to
meet the middle is that happening or or
what do you think uh well in the rest
frame it's staying at rest so you don't
need that explanation and it almost
makes the most sense just to consider in
our frame of reference nothing has
changed at the bottom until the top of
the slinky compressors true why not just
take gravity out of the equation Al
together and let's see what happens to a
horizontal Slinky all right let's have a
look at that okay this was prepared by
Rod earlier when I hit the right hand
end of the spring the left hand end
doesn't move until the compression wave
travels down the length of the spring
and changes the tension at that end yeah
so it's about the same thing as the
slinky but obviously there's no
gravitational force involved there
correct cool all right well thanks so
much we have learned a lot about
slinkies my
pleasure
sh