Author Topic: vectors- As physics  (Read 1668 times)

Offline Sue T

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vectors- As physics
« on: December 13, 2009, 01:45:22 pm »
does any1 have any notes for vectors? cuz they're really tricky! :o
Knowledge is knowing a tomato is a fruit; Wisdom is not putting it in fruit salad.

nid404

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Re: vectors- As physics
« Reply #1 on: December 13, 2009, 01:53:51 pm »
Vectors for AS physics are really easy....just work on sums in ur text and past papers...if u don't get any post them here, and we'll do it for u

I will look for notes on vectors anyway...try S-cool Physics...maybe that'll help

nid404

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Re: vectors- As physics
« Reply #2 on: December 13, 2009, 01:55:26 pm »

nid404

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Re: vectors- As physics
« Reply #3 on: December 13, 2009, 01:56:45 pm »
oh & if u want me to give u questions to do...I'll be glad to help and c how much you could do by yourself....lemme knw  :)

Offline girl_92

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Re: vectors- As physics
« Reply #4 on: December 13, 2009, 06:00:25 pm »
nid can u solve this 4 me i have an exam tommorow i wuld be relli thnkful
a student standin on a railway platform notices tth the first two carriages of an arriving train passes her in 2 sec and the nxt two in 2.4 s
the train is decelaratin uniformly.each carriage is 20m long when the train stops the student is opposite the last carriae how many carriages are there in the train
some people sleep to dream while othrs wakeup to follow dem im the second type how abt u

Offline astarmathsandphysics

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Re: vectors- As physics
« Reply #5 on: December 14, 2009, 08:30:58 am »
When i get up

Offline astarmathsandphysics

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Re: vectors- As physics
« Reply #6 on: December 14, 2009, 10:28:49 am »
Use s=ut+1/2at^2 twice

For the first two carriages
40=2u+2a
For the first for carraiges
80=4.4u+9.68a
Solve thes to get u=710/33
a=-50/33
then train takes s=(v^2-u^2)/2a=(710/33)^2/(2*50/33)=148.9
8 carrariages

Offline Sue T

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Re: vectors- As physics
« Reply #7 on: December 14, 2009, 02:12:21 pm »
thank you so much
 i'll study from the website u gave then if u can upload the questions it'll be great cuz i do need some practice :D
Knowledge is knowing a tomato is a fruit; Wisdom is not putting it in fruit salad.

Offline girl_92

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Re: vectors- As physics
« Reply #8 on: December 15, 2009, 07:46:34 am »
Use s=ut+1/2at^2 twice

For the first two carriages
40=2u+2a
For the first for carraiges
80=4.4u+9.68a
Solve thes to get u=710/33
a=-50/33
then train takes s=(v^2-u^2)/2a=(710/33)^2/(2*50/33)=148.9
8 carrariages
Thanks  alot sir
some people sleep to dream while othrs wakeup to follow dem im the second type how abt u