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# M1 moments Tweet

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1. M1 moments
The question is:

'A uniform rod AB has length 5m and weight 20N. The rod is resting on supports at points C and D where AC = 2m and BD = 1m.'

a) Find the magnitudes of the reactions at C and D:

I found Rc = 15N, Rd = 5N

b) A particle of weight 12N is placed on the rod at point A. Show that this causes the rod to tilt about C:
Eventually ended up with 24>10

c) A second particle of weight 12N is placed on the rod at E to hold it in equilibrium. How far must E be from A?:

Can't get this one for some reason.
2. Re: M1 moments
(Original post by najinaji)
The question is:

'A uniform rod AB has length 5m and weight 20N. The rod is resting on supports at points C and D where AC = 2m and BD = 1m.'

a) Find the magnitudes of the reactions at C and D:

I found Rc = 15N, Rd = 5N

b) A particle of weight 12N is placed on the rod at point A. Show that this causes the rod to tilt about C:
Eventually ended up with 24>10

c) A second particle of weight 12N is placed on the rod at E to hold it in equilibrium. How far must E be from A?:

Can't get this one for some reason.

In part (b), you have to show that is negative.

Part (c),

In part (b) it was tilting about C, so now to hold it, we have put added another particle to keep it in equilibrium. Now the rod is just about to tilt to about C, so equals zero, now resolve about C to find the answer.
Let AE be

Do i make any sense?