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# This moments question is driving me INSANE watch

1. prntscr.com/h11vtn

I have spent at least 50 minutes on it and I can't seem to get the correct answer. Help is VERY much appreciated if you can

Thank you.
2. (Original post by Xopic)
prntscr.com/h11vtn

I have spent at least 50 minutes on it and I can't seem to get the correct answer. Help is VERY much appreciated if you can

Thank you.
Can u post a proper link or picture of the question?
3. (Original post by Shaanv)
Can u post a proper link or picture of the question?
The link they've posted works, just copy and paste it into the searchbar of your internet browser.
4. (Original post by Xopic)
prntscr.com/h11vtn

I have spent at least 50 minutes on it and I can't seem to get the correct answer. Help is VERY much appreciated if you can

Thank you.
Hey. This question has a lot of information, and the diagram they've given isn't very helpful.

I would begin by drawing a long horizontal rod, labelled length 8.4m and with its weight acting at its centre of mass (we can assume this is in the middle, so 4.2m from castle).

Then add on all the other forces: vertical normal force at castle () and river bank (), horse's weight of 3200N acting downwards 2.1m from castle and drawbridge force (400N) acting at an angle of 35 degrees from 0.2m right of river bank.

Once you've got a good diagram, begin the questions.

For the first question, take moments about the pivot at the castle and hence solve for . Take care with all the distances and use the vertical component of the drawbridge's force.

For the second question, take moments about any of the other points where a force acts and hence solve for
5. (Original post by K-Man_PhysCheM)
Hey. This question has a lot of information, and the diagram they've given isn't very helpful.

I would begin by drawing a long horizontal rod, labelled length 8.4m and with its weight acting at its centre of mass (we can assume this is in the middle, so 4.2m from castle).

Then add on all the other forces: vertical normal force at castle () and river bank (), horse's weight of 3200N acting downwards 2.1m from castle and drawbridge force (400N) acting at an angle of 35 degrees from 0.2m right of river bank.

Once you've got a good diagram, begin the questions.

For the first question, take moments about the pivot at the castle and hence solve for . Take care with all the distances and use the vertical component of the drawbridge's force.

For the second question, take moments about any of the other points where a force acts and hence solve for
For part 2, while you are very correct of course, the idea of the second question (as you would see in many others) is to test one's knowledge of Equilibrum of forces.

"the algebraic sum of forces must be equal to zero."

So having found Nr, Nc is obtained by finding the Equilibrant of the forces.

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