Author Topic: M1 doubt .. URGENT..  (Read 995 times)

Offline crazed2009

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M1 doubt .. URGENT..
« on: April 17, 2010, 08:47:55 am »
hey can smone plz help me with this...

Figure 3 ( attachment) shows a particle X of mass 3 kg on a smooth plane inclined at an angle 30° to the
horizontal, and a particle Y of mass 2 kg on a smooth plane inclined at an angle 60° to the
horizontal. The two particles are connected by a light, inextensible string of length 2.5 metre
passing over a smooth pulley at C which is the highest point of the two planes.
Initially, Y is at a point just below C touching the pulley with the string taut. When the
particles are released from rest they travel along the lines of greatest slope, AC in the case of
X and BC in the case of Y, of their respective planes. A and B are the points where the planes
meet the horizontal ground and AB = 4 metres.

initial acceleration of the system is given by : g/10(2x3^0.5 -3)

    By finding the tension in the string, or otherwise, find the magnitude of the force
exerted on the pulley and the angle that this force makes with the vertical.


thanks,,
« Last Edit: April 17, 2010, 08:50:51 am by crazed2009 »

Amr Fouad

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Re: M1 doubt .. URGENT..
« Reply #1 on: April 17, 2010, 08:51:49 am »
7 minutes

Amr Fouad

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Re: M1 doubt .. URGENT..
« Reply #2 on: April 17, 2010, 09:04:12 am »
please post original question..i cudnt figure out whether the multiplied part of acceleration is with the num or denom

Offline crazed2009

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Re: M1 doubt .. URGENT..
« Reply #3 on: April 17, 2010, 09:10:48 am »
Q. 7  b)

Amr Fouad

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Re: M1 doubt .. URGENT..
« Reply #4 on: April 17, 2010, 09:17:23 am »
Thanks..give me some time..

Amr Fouad

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Re: M1 doubt .. URGENT..
« Reply #5 on: April 17, 2010, 09:28:37 am »
it gets really simple now..

first, you have got to find the tension:
T=3gsin30+3a
or
T=2gsin60-2a

then there's a genral rule to find normal force on pulley:

R=T x square root{2(1+cos theta)}

where theta equals the angle between the two ropes, int his case 90 degrees..

Try it..

Offline vanibharutham

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Re: M1 doubt .. URGENT..
« Reply #6 on: April 17, 2010, 09:36:49 am »
You have to consider it as pythagoras :P

or just learn this formula:

THE REACTION ON A PULLEY BY STRING = 2 x TENSION cos ( 90 - theta / 2 ), where theta is angle of slope

A genius is 1% intelligence, 99% effort.

Amr Fouad

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Re: M1 doubt .. URGENT..
« Reply #7 on: April 17, 2010, 09:37:41 am »
You have to consider it as pythagoras :P

or just learn this formula:

THE REACTION ON A PULLEY BY STRING = 2 x TENSION cos ( 90 - theta / 2 ), where theta is angle of slope



mine is easier :P..and works all the time :P

Offline crazed2009

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Re: M1 doubt .. URGENT..
« Reply #8 on: April 17, 2010, 09:49:36 am »
Thanks a LOT guys... :D its weird we never took these formulas, nt tht i remeber at least..
but wht about the rest of the question.. the angle btn the force and the vertical???