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Moments question

A uniform rod is balanced horizontally about a support F. Forces of 400 N and 100 N act at the ends of the rod, as shown.

What is the reaction force acting on the rod at support F?
Sum of anti clock wise moments = sum clockwise moments I tried using this but my answer comes out as 533N and the mark scheme says 600N I have tired making two equations from either point but can't get the answer
(edited 2 years ago)

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What have you done so far
Original post by Qxi.xli
What have you done so far

tried taking moments from either end of the beam and solving for Rf but still not right
Original post by as2curry:
A uniform rod is balanced horizontally about a support F. Forces of 400 N and 100 N act at the ends of the rod, as shown.

What is the reaction force acting on the rod at support F?
Sum of anti clock wise moments = sum clockwise moments I tried using this but my answer comes out as 533N and the mark scheme says 600N I have tired making two equations from either point but can't get the answer

Does the question state the weight of the rod?
Original post by Qxi.xli
Does the question state the weight of the rod?

No it does not just says its a uniform rod
Original post by as2curry:
No it does not just says its a uniform rod

Hmm
What exactly is your equation for anticlockwise=clockwise? x
Yeah sum of anti clockwise = clockwise
Original post by as2curry:
Yeah sum of anti clockwise = clockwise

Post your working and the full question
Original post by Muttley79
Post your working and the full question

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Original post by as2curry:
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Your working?
Original post by Muttley79
Your working?

Cant really upload my working but could you explain what you would do if that is possible
Don't have my book with me
(edited 2 years ago)
Original post by as2curry:
Cant really upload my working but could you explain what you would do if that is possible

I took moments about both ends.

Type or photo your work
Original post by Muttley79
I took moments about both ends.

Type or photo your wo

f+300 = FD
3f+400 = FD
Original post by Muttley79
I took moments about both ends.

Type or photo your work

Lol now I'm confused about the question too😭
Is the reaction force an anticlockwise or clockwise moment?

Original post by as2curry:
f+300 = FD
3f+400 = FD

Is the answer A
(edited 2 years ago)
Original post by as2curry:
f+300 = FD
3f+400 = FD

Moments about left end? Sorry what is FD? You can take moments about the centre too.
Original post by Qxi.xli
Lol now I'm confused about the question too😭
Is the reaction force an anticlockwise or clockwise moment?


Is the answer A

Mark Scheme says D 600n
Original post by Muttley79
Moments about left end? Sorry what is FD? You can take moments about the centre too.

What was your working out when you did it through the centre?
Original post by as2curry:
What was your working out when you did it through the centre?

We can't post solutions - please just explain what you posted and I'll give you a hint to correct it
Original post by as2curry:
Mark Scheme says D 600n

Yea I got that
Original post by Muttley79
Yea I got that

did you take moments from F?