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Please, I am in need of help. I'm having difficulty in answering this question: "Two tugboats towing a barge exert a force of 5.0 N each. If the angle between two ropes is 30 degrees, what is the resultant force exerted on the barge?"

 

Anyone willing to help me with this + showing it thru graphing?

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Try to describe how you would try to solve this.

 

ps 5.0N - pretty useless tugs!

Yeah, I hate it when teachers are too lazy to look up proper numbers. They could teach students a feeling for numbers at the same time as teaching them the theoretical stuff, but no.

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Try to describe how you would try to solve this.

 

 

Yeah, I hate it when teachers are too lazy to look up proper numbers. They could teach students a feeling for numbers at the same time as teaching them the theoretical stuff, but no.

Although the tug firms are lazy in other ways - the bollard pull is nearly always quoted in tons. Most of the time this is not made clear whether it is long tons (which is technically a weight and okish) or they mean metric tonnes - and that's a mass not a force.
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It would be a funny calculation to find out how long it would take a tug to move an oil tanker of 500,000 ton, if it exerts a force of 5 N. :)

 

If F = m*a, and F = 5 N, and m = 500,000,000 kg, then:

 

a = F/m = 5/500,000,000 = 0.00000001 m/s2.

 

That would mean that it takes:

 

xt = 0.5*a*t^2, so:

t = sqrt(xt/(0.5*a)) = sqrt(1/(0.5*0.00000001))=14142 seconds, or nearly 4 hours.

 

Since in

, a tug will need seconds to do that - minutes if they're being careful - we can conclude that the force is severely underestimated.

 

Let's say they need 60 seconds to get it to move...

a = 1/(0.5*60^2)=0.0006 m/s2

So:

F = m*a = 500,000,000*0.0006 = 277,000 N.

 

(A quick check online for tugs says that this number is closer to the truth than the 5N we had in the assignment).

 

And that is how you take a thread completely off topic. :)

(let's get back on topic, shall we?)

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!

Moderator Note

Fuzzwood, that was a spammer wanting traffic for some silly website, next time just report it and the moderators will do the rest.

To everyone else: if you don't understand what we're talking about, that is because I just deleted that post.

Nothing to see here, move along, move along. Let's get back on topic.

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Please, I am in need of help. I'm having difficulty in answering this question: "Two tugboats towing a barge exert a force of 5.0 N each. If the angle between two ropes is 30 degrees, what is the resultant force exerted on the barge?"

 

Anyone willing to help me with this + showing it thru graphing?

 

 

 

Why is there a presumption of mistaken forces ? The original poster asks a question with two forces each of 5.0N, two 5.0N forces applied to a small floating model in a classroom at an elementary level could be quite understandable.

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