Take the Einstein Challenge

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Take the Einstein Challenge
So you think you are as clever as me?
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Einstein started thinking...
I wonderWhat would it be like to catch up with a
beam of light?
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Question 1

• HOW FAST DOES LIGHT TRAVEL IN EMPTY SPACE
• (in a vacuum)?
• A. 300000 km per second
• B. It varies
• C. 300 km per second

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Answer 1 A

• Speed of light is 300000 km per second
• Thats
• 7 times around
• the world in
• one second !

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Question 2

• Imagine youve decided to find out what it is
  like to catch up with a beam of light. You build
  a super rocket with limitless fuel.
• You are in deepest outer space so there is
  nothing to bump into, and you have all the time
  you could possibly need.
• You start the enginesyou go faster and faster.
• WOULD YOU BE ABLE TO CATCH UP WITH AND OVERTAKE
  A BEAM OF LIGHT?

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Options

• A. Engines create a pushing force causing you to
  speed up. Its only a matter of time before the
  rocket will reach 300000 km per second.
• B. No, it is just impossible for anything to
  travel faster than the speed of light
• C. It could if it wasnt for friction. As your
  rocket goes faster and faster friction gets
  greater and greater creating a breaking effect
  that cancels out the engine thrust.

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Answer 2 B

• Einstein realised that nothing could travel
  faster than the speed of light.
• As you will discover amazing things happen to a
  rocket (or any material object) that tries to get
  close to the speed of light.
• What happens? Well first a little detour

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Question 3

• Einstein is famous for the equation
• Emc²
• What does each letter stand for?

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Options

• A E energy mmass
• c speed of light
• B E energy mmass c current
• C E electric charge mmass c
  speed of sound

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Answer 3 A

• This equation doesnt look special but if you
  understand it, it tell us something
• AMAZING!

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Our common sense tell us that everything we
encounter can be divided into TWO groups

• Energy

Matter
OR
Like heat and light, movement.. The stuff that
makes things happen
Like you, the table, the earth.. The stuff that
things are made of
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What Emc2 is telling us is that

• ENERGY CAN SOMETIMES TURN INTO

energy
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What is telling us is that

• ENERGY CAN SOMETIMES TURN INTO MATTER

energy
Matter is the stuff that you and I are made of
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and the other way around.MATTER CAN SOMETIMES
CHANGE INTO
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and the other way around.MATTER CAN SOMETIMES
CHANGE INTO PURE ENERGY
energy
Sounds like magic ????
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Question 4

• Back to our rocket.what happens to the rocket
  to make it impossible to catch up with light?
• Guess which answer Einstein would give.

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Options

• As the rocket goes faster and faster
• A The rocket loses mass (could say it gets
  lighter) and therefore loses energy and cant
  speed up
• B The rockets mass is unchanged
• C The rocket gains mass (could say it gets
  heavier) so it becomes increasingly harder to
  speed it up.

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Answer 4 C

• Einstein worked out that as material starts to
  move it gains more mass (in simple termsit gets
  heavier)
• The faster you move the greater the gain in mass

• Every part of your rocket (including you if you
  are on it) gains more and more mass as you go
  faster and faster

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.Why is it so hard to get a large truck moving
by pushing it?
Why does an increase in mass stop you catching up
with light???

• ..because its got lots of mass
• The more mass an object has the more energy it
  takes to speed it up.

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Einstein worked out

• In attempting to reach the speed of light your
  mass will become INFINITE!
• All the energy of in the universe would not be
  enough to speed up an object to catch up with
  light, never mind overtake it.

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Question 5

• Imagine you are standing on earth watching
  someone move past you in their space rocket.
• They are travelling at a steady speedabout
  120000km per second (nearly half the speed of
  light).
• Einstein reasoned that you would notice something
  else strange happening to the rocketWhat is it?

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Options

• A The space rocket and everything in it would
  appear to shrink in the direction it was
  travelling in.
• B The space rocket and everything in it would
  appear to expand in the direction it was
  travelling in.
• C The space rocket would appear to expand in all
  directions

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Answer 5 A
From where you are standing
The rocket would appear to
Shorten
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Answer 5 A
From where you are standing
The rocket would appear to
Shorten
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Strangely

• The person in the spaceship cannot see the
  shrinking. Everything looks normal to them.
• Everything they measure with a ruler appears to
  be the same length as before.

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Question 6

• Why would their ruler not show up the change?
• A Rulers are no use in space
• B The ruler is not accurate enough to measure
  any change
• C The ruler shrinks too and so measurements look
  the same

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Answer 6 C

• The ruler shrinks too

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The super brainy part is
E mc2

• Einstein realised that its not just the rocket,
  ruler etc. that shrinks..
• You are seeing SPACE ITSELF SHRINKING!!!
• Thats hard to get your head around .unless of
  course you are Einstein!

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Question 7

• If Einstein is right then every time we move
  (according to measurements taken by someone
  watching us) we gain mass and shrink (in the
  direction of motion).
• How come none of us have never noticed?
• A People are too busy to notice.
• B At everyday speeds the gain in mass and
  shrinking is so small we cannot measure it
• C Because Einstein was obviously wrong

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Answer 7 B

• You have to achieve colossal speeds (close to the
  speed of light) for these effects to become
  measurable.
• NOW FOR ANOTHER MIND BOGGLING QUESTION.

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QUESTION 8
You ask such tricky questions !!!!

• IS TIME TRAVEL POSSIBLE?

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Options

• A Yes you can travel backwards and forwards in
  time.
• B You can only travel forward in time, not back.
• C No

Guess what I think
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Answer 8 B

• Surely time iswelltime! You cant change
  it. It must be the same everywhere????

• Einstein reasoned that TIME DOES CHANGE
  depending on
• How you are moving and
• Where you are in the universe

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Question 9

• Lets go back to watching our spaceship from
  earth So far we have seen it gain in mass and
  shrink
• Einstein says there is something else you will
  see.something to do with TIME.
• What is it?

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Options

• A Everything inside the rocket appears to
  happen in slow motion..time slows down!
• B Everything appears to be speeded up..time
  speeds up!
• C Everything happening in the rocket appears to
  be going backwards..time is in reverse.

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Answer 9 A

• The passenger on the rocket is completely unaware
  of time slowing down
• ..Their brain processes have slowed down too!

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Travelling at steady high speeds is one thing but
if you really want to mess with time you need to
know more.

• First a definition (to a physicist)
• ACCELERATION means.
• Speeding up/ slowing down/ changing direction.

• If you really want to travel in time Einstein
  would suggest that you go on a journey that
  involves colossal rates of acceleration!

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Imagine if

• You had a twin.
• you go on a white knuckle ride on your space
  rocket (lots of accelerating) for a number of
  years, whilst your twin stays behind
• EINSTEIN CLAIMS THAT WHEN YOU GET BACK.

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You would not have aged as much as your twin

• Back from your trip!

• The twin who stayed at home!

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Question 10

• Einstein says that when you accelerate
• time slows down.
• On your recent space rocket ride. in which
  direction have you travelled in time?
• A Forward in time
• B Backwards in time
• C You havent travelled in time at all its just
  an illusion.

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Answer 10 A

• You have travelled into your twins future!
• but Einstein realised that there was more to
  time travel than hair raising spaceship rides.

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Question 11

• Something else can slow down time. What is it ?
• A Electricity
• B Magnetism
• C Gravity

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Answer 11 C

• Gravity

• The strength of gravity on the earths surface
  slows down our clocks by about 1 second every
  century.

• Scientists have put clocks on high flying
  planes (high up gravity is weaker) and they come
  back having gained a tiny bit of a tick

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For serious time travel you need BIG GRAVITY!

• The more mass something has the bigger its
  gravitational pull
• You need something like a BLACK HOLE !!!
  The gravity monsters of the universe

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So now you know why Einstein is a GENIUS

• Sitting at his desk he carried out
• thought experiments
• That led him to conclude that

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That Space and Time are not as simple as our
everyday experience suggests!

• Spacetime
• (as Einstein called it) can
• Its not science fiction but real physics!

Warp
Stretch

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Congratulations on completing the Einstein
Challenge
Anyone who has never made a mistake has never
tried anything new!
Time for one last challenge ?
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Try a bit of free thinking

• Weve been watching our friend moving past us in
  a space rocket at nearly half the speed of
  light.
• We understand that we will see
• Their MASS increase
• Their LENGTH shrink
• Their TIME slow down
• The question is

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When your friend looks out of her window at you

• HOW DO YOU LOOK TO HER?
• Will she see any difference in your
• MASS, LENGTH and TIME?
• What do you think?

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