Spotty's Little Known Facts

[LeverEnd]

That wasn't on Mythbusters so I have no idea.

[thebish]

Right. Now if I walk at 3 mph up the aisle of a train travelling at 100mph am I travelling at 103 mph?

if measured by someone on the train - no. if measured by someone who is stationary outside the train - then, yes.

See, you've fallen into the trap of assuming that he's walking in the same direction as which the train is headed.

arse!!

[jaffka]

So, is it 3mph, -97mph or 103mph?

[Gary the Enfield]

Right. Now if I walk at 3 mph up the aisle of a train travelling at 100mph am I travelling at 103 mph?

if measured by someone on the train - no. if measured by someone who is stationary outside the train - then, yes.

See, you've fallen into the trap of assuming that he's walking in the same direction as which the train is headed.

arse!!

[Montreal Wanderer]

The amount of downward force exerted by the birds' wings on the air to keep them up there is equal to the weight of the bird, so the weight is effectively transferred through the air to the floor of the truck and keeps the overall weight the same. Yes it has to be closed.

This question (or similar) was asked many years ago on a British program called "Don't ask me" and was explained by the boffin host Magnus Pyke. He put a very large (six foot long) model helicopter on a large scale in the TV studio. When the helicopter took off the weight increased as it rose then returned to the original figure as it hovered. Unfortunately at the this point the technician handling it lost control and it buzzed around the studio terrifying the audience briefly.

Along similar lines I'll pose a problem. There is a barge in a closed (hermetically sealed) lock on a canal. In the barge there are two tons of iron ingots. Someone tosses them all overboard. Does the water level in the lock go up, down or stay the same?

[PC1978]

I would say Eureka! and go for the same.

[Worthy4England]

I'm wondering why anyone would be alive to throw them anywhere if it's hermetically sealed.

[Montreal Wanderer]

I'm wondering why anyone would be alive to throw them anywhere if it's hermetically sealed.

Scuba gear - only sealed for the time it takes to toss the stuff overboard! Now, answer the question!

[Prufrock]

Stay the same is my reckon.

The 'rise' in the water level being offset by a smaller amount of boat being below the water line and so displacing less.

[Montreal Wanderer]

Stay the same is my reckon.

The 'rise' in the water level being offset by a smaller amount of boat being below the water line and so displacing less.

Two for stay the same. I'll leave it open a little longer.

[Gary the Enfield]

Stay the same is my reckon.

The 'rise' in the water level being offset by a smaller amount of boat being below the water line and so displacing less.

Two for stay the same. I'll leave it open a little longer.

I'm of the same opinion. So go on, how wrong are we three and why?

[Montreal Wanderer]

Stay the same is my reckon.

The 'rise' in the water level being offset by a smaller amount of boat being below the water line and so displacing less.

Two for stay the same. I'll leave it open a little longer.

I'm of the same opinion. So go on, how wrong are we three and why?

Well, you are indeed all wrong. The answer is that though the barge rides higher in the water (thus displacing less) the water level goes down. Why? When the iron ingots are in the barge they displace their mass, but when they are in the bottom of the lock they displace only their volume. Being heavy buggers the displacement of their mass is far greater than that of their volume.

Which reminds me of the woman who said she wanted to lose weight. The replay was "No, you want to lose mass. If you want to lose weight, go to the moon."

[PC1978]

Stay the same is my reckon.

The 'rise' in the water level being offset by a smaller amount of boat being below the water line and so displacing less.

Two for stay the same. I'll leave it open a little longer.

I'm of the same opinion. So go on, how wrong are we three and why?

Well, you are indeed all wrong. The answer is that though the barge rides higher in the water (thus displacing less) the water level goes down. Why? When the iron ingots are in the barge they displace their mass, but when they are in the bottom of the lock they displace only their volume. Being heavy buggers the displacement of their mass is far greater than that of their volume.

Which reminds me of the woman who said she wanted to lose weight. The replay was "No, you want to lose mass. If you want to lose weight, go to the moon."

Thought of that but ruled it out as I was thinking I was over-complicating matters!

[Lost Leopard Spot]

The US Postal Service becomes the latest institution in America to arm its agents with hollow point bullets (the sort that Oscar Pistorius fired and killed Reeva Steenkamp with).
The list of US government agencies that use them includes
The CIA
The FBI
Homeland Security
Bureau of Alcohol Tobacco and Firearms
Social Security Administration
National Aeronautics and Space Administration
National Oceanic and Atmospheric Administration
and the Department of Agriculture - (who also placed an order for 4,000 submachine guns back in May)

[source Washington Times 16/May/2014]

[Beefheart]

The US Postal Service becomes the latest institution in America to arm its agents with hollow point bullets (the sort that Oscar Pistorius fired and killed Reeva Steenkamp with).
The list of US government agencies that use them includes
The CIA
The FBI
Homeland Security
Bureau of Alcohol Tobacco and Firearms
Social Security Administration
National Aeronautics and Space Administration
National Oceanic and Atmospheric Administration
and the Department of Agriculture - (who also placed an order for 4,000 submachine guns back in May)

[source Washington Times 16/May/2014]

When we went to a shooting range in West Virginia, the guy showed us that his pistol had hollow point ammunition, he explained that as the bullet hits someone it expands causing a huge amount of internal damage, then went on to say that it was 'self defence ammunition', when we asked how on earth it could be called that he said, 'well, it means it won't go out of the back of the guy you're shooting and hit someone else'. That's ok then.

[Montreal Wanderer]

The US Postal Service becomes the latest institution in America to arm its agents with hollow point bullets (the sort that Oscar Pistorius fired and killed Reeva Steenkamp with).
The list of US government agencies that use them includes
The CIA
The FBI
Homeland Security
Bureau of Alcohol Tobacco and Firearms
Social Security Administration
National Aeronautics and Space Administration
National Oceanic and Atmospheric Administration
and the Department of Agriculture - (who also placed an order for 4,000 submachine guns back in May)

[source Washington Times 16/May/2014]

When we went to a shooting range in West Virginia, the guy showed us that his pistol had hollow point ammunition, he explained that as the bullet hits someone it expands causing a huge amount of internal damage, then went on to say that it was 'self defence ammunition', when we asked how on earth it could be called that he said, 'well, it means it won't go out of the back of the guy you're shooting and hit someone else'. That's ok then.

In the old days they used to hollow the point by carving out a cross on the point, causing the bullet to expand on impact. These were called dum-dums after some arsenal in India. I suspect expanding bullets have been around a long time. Nasty things.

[Lost Leopard Spot]

I just don't get why they should be arming postal workers with dumdum bullets and why the Department of Agriculture needs four thousand submachine guns. I've just never considered wheat or parcels to be that revolutionary!

[Prufrock]

They probably need them to deal with crazy hick farmers armed with shotguns to fight off any interference by the state!

[Montreal Wanderer]

I just don't get why they should be arming postal workers with dumdum bullets and why the Department of Agriculture needs four thousand submachine guns. I've just never considered wheat or parcels to be that revolutionary!

I was curious and tried to look up the reason. All source say the number of SMGs requested is unknown - not 4000. Possibly the fact they wanted .40 calibre ammunition confused things. The actual request was as follows:

“Submachine guns, .40 Cal. S&W, ambidextrous safety, semi-automatic or 2 shot burts trigger group, Tritium night sights for front and rear, rails for attachment of flashlight (front under fore grip) and scope (top rear), stock-collapsilbe or folding, magazine – 30 rd. capacity, sling, light weight, and oversized trigger guard for gloved operation.”

[bobo the clown]

I just don't get why they should be arming postal workers with dumdum bullets and why the Department of Agriculture needs four thousand submachine guns. I've just never considered wheat or parcels to be that revolutionary!

I was curious and tried to look up the reason. All source say the number of SMGs requested is unknown - not 4000. Possibly the fact they wanted .40 calibre ammunition confused things. The actual request was as follows:

“Submachine guns, .40 Cal. S&W, ambidextrous safety, semi-automatic or 2 shot burts trigger group, Tritium night sights for front and rear, rails for attachment of flashlight (front under fore grip) and scope (top rear), stock-collapsilbe or folding, magazine – 30 rd. capacity, sling, light weight, and oversized trigger guard for gloved operation.”

At first I read that as being that it was the post-men who had .4 calibre semi-automatic sub-machine guns with night vision telescopic sights.

I now realise that it's the Agriculture guys. Phew. I as worried for a minute.

I suppose they may go on narcotics growing raids.