[chris (OP)]

We received some great questions on the radio show on Monday from the inhabitants of Essex. I've listed a few of them here to tickle your fancy. I thought we could debate the answers amongst ourselves.

1) Roger - "Why don't you get an electric shock from a train"

2) John - "Any link between herbal tea and erosion of tooth enamel?"

3) Anne - "Does aspartame cause bladder cancer ?"

4) ?someone - "Why do stars twinkle, but not planets ?"

5) Mary - "Why is the moon visible in the day time?"

6) Brian - "Can flies really take off backwards ?"

7) ? - "Is it true that fishing bait contains marijuana?"

Be interested in what you lot think about the answers to these !

Chris

[Exodus]

I'm pretty sure i've heard that flies can take off backwards.... might explain why you can never splat them!

Essentia non sunt multiplicanda praeter necessitatem...

[Dickie]

Cars build up static as they drive (similar to rubbing a balloon against yourself). You don't get the same charge build-up, as you are insulated from the car (fabric seats). Therefore, by the time the car stops, it is at a different potential to you. It is insulated from ground because of the rubber tyres, so the excess charge can't go anywhere. When you touch the metal of the car, the difference in potential causes a brief current, which can sometimes hurt.

A train has metal wheels, so doesn't build up charge.

[Dickie]

The light travels a huge number of light years to us with no problems whatsoever, then gains a twinkle in the last few miles as a result of the atmosphere. This is why the best pictures of space come from telescopes high up- either on the top of a mountain, or in orbit.

Planets really ought to suffer the same effect. Maybe because they look bigger the naked eye can't see the twinkle.

[cuso4]

We see the moon because it reflects the light from the sun. When moon is visible during daytime that's when it is at position where it reflects sunlight which then enters your eye.

Angel

[cuso4]

Aeroplanes also build up static during flights, this is why it needs to be discharged when fueling the aircraft because a spark could easily cause explosion.

Angel

[chris (OP)]

Phew, that's a relief, looks like I answered most of them correctly.

Dickie - don't suns also twinkle a little bit because the light they emit is bent by giant planets in orbit around them (gravitational lensing) ?

Chris

[Dickie]

Gravitational lensing only really becomes an issue when there's something REALLY HEAVY between the star and us, such as a black hole. I managed to avoid general relativity courses, so I can't really speak as an expert, but I seem to remember hearing about a star that could be seen next to itself because the light travelled both ways around something big and heavy.

[Dickie]

Same problem with helicopters. If you're being rescued, you should let the ladder touch the ground before grabbing it.

[chris (OP)]

quote:Originally posted by Dickie

Same problem with helicopters. If you're being rescued, you should let the ladder touch the ground before grabbing it.

So what about when they lower someone down from the helicopter then - presumably they'll get a shock when they hit the ground ?

Chris

[Exodus]

quote:Originally posted by chris

quote:Originally posted by Dickie

Same problem with helicopters. If you're being rescued, you should let the ladder touch the ground before grabbing it.

So what about when they lower someone down from the helicopter then - presumably they'll get a shock when they hit the ground ?

Chris

not if you jump from the ladder rather than step down or vice versa... []

Essentia non sunt multiplicanda praeter necessitatem...

[chris (OP)]

But what about a sea-rescue where they're hooked on ?

Chris

[Exodus]

erm..... rubber soled boots? stops them from earthing?

Resident Tour Operator - The Naked Scientists

[Exodus]

quote:Originally posted by chris

We received some great questions on the radio show on Monday from the inhabitants of Essex. I've listed a few of them here to tickle your fancy. I thought we could debate the answers amongst ourselves.

1) Roger - "Why don't you get an electric shock from a train"

2) John - "Any link between herbal tea and erosion of tooth enamel?"

3) Anne - "Does aspartame cause bladder cancer ?"

4) ?someone - "Why do stars twinkle, but not planets ?"

5) Mary - "Why is the moon visible in the day time?"

6) Brian - "Can flies really take off backwards ?"

7) ? - "Is it true that fishing bait contains marijuana?"

Be interested in what you lot think about the answers to these !

Chris

Did somebody really ask question 7??! Oh my god!

Is it true?

Resident Tour Operator - The Naked Scientists

[chris (OP)]

mmm no one has properly answered the issue of flies taking off backwards yet either...any suggestions or sites that anyone knows of that deals with this ?

[Exodus]

i'm sticking with  the idea that flies do take off backwards..... but then i'm drunk. anyone want to try and prove me wrong???

Resident Tour Operator - The Naked Scientists

[nilmot]

This is a theory,

Flies might be able to take off backwards. They have tiny body weight and their wing spand is wide enough to create an air-resistance, which with this force will be able to push their body backwards.

Not [?] sure [?]

Tom

[Donnah]

I've seen flies take off backwards (there's that backwards thing again Chris...don't take it personally).  It's much easier to catch them (or squish[}:)] them) when you know that's what they're going to do.

[teeroman]

Oh Yah....well my grandpa has been trying to teach pigs to fly for 50 years..ever since grandma told him he could have two wives 'WHEN PIGS FLY', poor man pretty near ate himself through a full acre of pig slop one year...he is cute my grandpa...but dumb as a puck....

[Donnah]

Did you hear the explanation of why Neil Armstrong said "Go for it Mr. Gorski!" when he landed on the moon?