Maths Question challenge!

Freya · Post by **Freya** » Mon Feb 09, 2009 10:50 am

DS sat maths, English and VR on Saturday. He came out very happy saying that maths was pretty easy, VR was very easy and English was not as hard as the last one he sat although he ran out of time with his story .

Anyway, this morning he casually asks "if you shot a bullet into the sky at an angle of 90 degrees and the bullet travelled at 50mph, how long would it take to come back down?" Apparently this was one of the maths questions

You had to provide an estimate for the answer.

Well, after waffling on about speed, distance and time and the bullet slowing down over time due to gravity and air resistance and considering terminal velocity on it's return path I realised I still didn't have a clue and we had arrived at school so I ran out of time! LOL

DS said "oh well, I put half an hour - I think it was just one of THOSE questions" in a very matter of fact tone and didn't seem at all bothered!

Surely there had to have been more info to the question? It's bothering me now!

Not in terms of DS getting it right or wrong - more like when you can't think of 'who sang that song'

Any ideas? Anyone want a challenge on a Monday morning?

mike1880 · Post by **mike1880** » Mon Feb 09, 2009 11:11 am

Blimey!

It's about 6-7 seconds but I had to use a calculator to sort out the hash I made of decimal places. I wouldn't expect even a bright 10/11 year old to have a clue, I imagine the idea is to use the answer as a basis for questions at interview later.

[edit - actually it's about 5 seconds, it helps if you don't mentally swap the digits round when doing the sums...

]

Mike

WP · Post by WP » Mon Feb 09, 2009 11:24 am

The bullet starts at 22.347 metres per second. If you ignore air resistance, it will decelerate due to gravity at 9.8 metres per second per second, so it will be stationary (at the top of its flight) after 2.28 seconds, and will be back at the start point in twice that time.

Freya · Post by **Freya** » Mon Feb 09, 2009 12:12 pm

Mike1880 and WP : thanks very much - I knew I could count on the brains in this forum to help me out!

Why is it that they ask you these questions on the way to school, soooooo early in the morning?

I'm normally not bad at difficult questions - DS has regularly asked questions such as "what keeps the stars from falling down" and "if we all came from the same place in Africa why do we all speak different languages" since the age of about 4.

A recent one was "If we were as small as a speck of dust, would we be able to see a molecule" and "If everyone in France stood on the coastline and jumped and shouted all at once, would someone standing on England's coastline be able to hear the sound or feel the vibration?"

What other 'difficult' questions have other people's DC asked? and What were your answers?

T.i.p.s.y · Post by **T.i.p.s.y** » Mon Feb 09, 2009 12:16 pm

Freya,

I am now seriously worried about what they may ask DS. I can't believe these questions were for an 11 year old!

Freya · Post by **Freya** » Mon Feb 09, 2009 12:34 pm

I've been alerted (quite rightly) to the possibility of having given away details of the exam on this post which would be unfair if there were any children taking the exam late due to various circumstances.

Can I reassure everyone that the Head confirmed all students taking the exam were present on the day. We asked out of interest due to the snow.

Loopyloulou · Post by **Loopyloulou** » Mon Feb 09, 2009 6:19 pm

Is this the same school as the one with the matchstick fish?? If so, it's a must!!

Freya · Post by **Freya** » Mon Feb 09, 2009 7:10 pm

LOL No it's the other one!

I think it was probably a case of throwing in a curve ball to see if anyone would catch it! Surprised DS didn't - he's a mean prospect with a spin pass!

SunlampVexesEel · Post by **SunlampVexesEel** » Mon Feb 09, 2009 8:16 pm

Freya wrote:I think it was just one of THOSE questions

I agree with DS. 50mph is far too slow for a bullet and Health and Safety wouldn't allow the experiment in the first place.

Should you send DS to a school that regularly uses firearms in Science lessons?

I would recommend DS to run slightly faster than his answer suggests... just in case.

Regards
SVE

PS

http://www.loadammo.com/Topics/March01.htm

solimum · Post by **solimum** » Mon Feb 09, 2009 8:47 pm

Freya wrote:Mike1880 and WP : thanks very much - I knew I could count on the brains in this forum to help me out!

DS has regularly asked questions such as "what keeps the stars from falling down" and "if we all came from the same place in Africa why do we all speak different languages" since the age of about 4.

A recent one was "If we were as small as a speck of dust, would we be able to see a molecule" and "If everyone in France stood on the coastline and jumped and shouted all at once, would someone standing on England's coastline be able to hear the sound or feel the vibration?"

Are you sure he's not moonlighting as an Oxbridge admissions tutor?!

Actually, I used to have deep conversations with my DS2 at that age about "the numbers going on for ever" and we were probably into countable and uncountable infinities at Juniors. He's now doing Maths at Oxford!

Maths Question challenge!

Maths Question challenge!

Re: Maths Question challenge!