Author Topic: All Mechanics DOUBTS HERE!!!  (Read 86387 times)

Offline Uchia

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Re: All Mechanics DOUBTS HERE!!!
« Reply #165 on: May 23, 2010, 09:58:24 am »
this one plz its urgent question 7

Offline Igcseboy

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Re: All Mechanics DOUBTS HERE!!!
« Reply #166 on: May 23, 2010, 09:59:23 am »
jan 2010 question 6 d.... plzzz

Offline astarmathsandphysics

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Re: All Mechanics DOUBTS HERE!!!
« Reply #167 on: May 23, 2010, 10:47:38 am »
q7

Offline astarmathsandphysics

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Re: All Mechanics DOUBTS HERE!!!
« Reply #168 on: May 23, 2010, 10:54:25 am »
jan 2010 question 6 d.... plzzz
before A hits It accelerates at g/4 for 1.2s
s=1/2at^2=1/2*g/4*1.2^2=0.18g
When A hits floor, it and B are travelling with speedv=at=g/4*1.2=0.3g
Now B moves freely under gravity
v^2=u^2+2as
0=(0.3g)^2+2*-g*s
s=0.045g
height reached=0.18g+0.045g=0.225g

Offline georgianna

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Re: All Mechanics DOUBTS HERE!!!
« Reply #169 on: May 23, 2010, 11:09:58 am »
has anyone done the M1 mock paper
http://www.srepapmaxeeeerf.org/A%20Level/Maths/Edexcel/M1/M1%20Mock.pdf
how do you get 8103.2 for 5c??
I only got 7280

Offline Uchia

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Re: All Mechanics DOUBTS HERE!!!
« Reply #170 on: May 23, 2010, 11:17:58 am »
yeah i solved that question many times and i went to conclusion that they made a mistake in there calculations even my teacher said the same thing. There answer seem very weird

Offline Uchia

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Re: All Mechanics DOUBTS HERE!!!
« Reply #171 on: May 23, 2010, 11:19:03 am »
hey guys plz help me in my doubt june 01 question 7

Offline astarmathsandphysics

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Re: All Mechanics DOUBTS HERE!!!
« Reply #172 on: May 23, 2010, 11:22:15 am »
For the M1 mock paper

speed of both togeter is 5.6*78/84=5.2
deceleration=5.2/0.06=87


use F=ma to get R-84g=84*87 so R=84g+86*87

Offline astarmathsandphysics

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Re: All Mechanics DOUBTS HERE!!!
« Reply #173 on: May 23, 2010, 11:25:23 am »
hey guys plz help me in my doubt june 01 question 7

Offline Uchia

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Re: All Mechanics DOUBTS HERE!!!
« Reply #174 on: May 23, 2010, 11:28:45 am »
thanks sir

Offline Uchia

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Re: All Mechanics DOUBTS HERE!!!
« Reply #175 on: May 23, 2010, 11:36:01 am »
how did you know that you need to add 6j in part a

Offline Igcseboy

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Re: All Mechanics DOUBTS HERE!!!
« Reply #176 on: May 23, 2010, 12:12:48 pm »
jan 2010 question 6 d.... plzzz
before A hits It accelerates at g/4 for 1.2s
s=1/2at^2=1/2*g/4*1.2^2=0.18g
When A hits floor, it and B are travelling with speedv=at=g/4*1.2=0.3g
Now B moves freely under gravity
v^2=u^2+2as
0=(0.3g)^2+2*-g*s
s=0.045g
height reached=0.18g+0.045g=0.225g

but its different in the markscheme :S:S:S

Offline perrychan527

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Re: All Mechanics DOUBTS HERE!!!
« Reply #177 on: May 23, 2010, 02:36:28 pm »
M1 Jan 08 6d plzz
dont understd the question and marking. thx..

Offline Saladin

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Re: All Mechanics DOUBTS HERE!!!
« Reply #178 on: May 23, 2010, 02:50:11 pm »
M1 Jan 08 6d plzz
dont understd the question and marking. thx..

answering now.

Offline Saladin

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Re: All Mechanics DOUBTS HERE!!!
« Reply #179 on: May 23, 2010, 02:53:28 pm »
I am going to have to answer the whole question, so please, it may take a while.