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Anonymous05/03/26, 00:57No.16969264
Can /sci/ help me with a problem. I understand and got correct question 2 but question 3 I would have guessed 50kg. I would have thought that due to the rope being pulled in the same direction as the load it becomes a supporting rope, therefore 300/6 rather than 300/5 to get 50kg of equivalent force to lift the weight. Can anyone help explain why the answer is 60kg?
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Anon05/03/26, 05:59No.16969381
It does, there's a mistake or at least some kind of dumb assumption in the question.
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Anon05/03/26, 15:43No.16969603
Divide the weight by the number of ropes that are shortening (the one you are holding lengthens as you pull more out from the first pulley).
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Anon05/03/26, 17:30No.16969641
It's 50Kg
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Anon05/03/26, 17:35No.16969644
>75 kg of force
>60 kg of force
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Anon05/04/26, 03:14No.16969865
It depends on the angles of the ropes.toss this book away because the author is stupid motherfucker
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Anon05/05/26, 10:48No.16970525
Just (((NOOOOTICE))) the patterns because you have high IQIn 2. its 75 because you have 5 ropes. You can get 75 by doing this: 300kg / (5ropes-1)
so in 3 just do the same thing 300kg / (6ropes - 1). Don't ask about the -1.
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Anon05/05/26, 16:40No.16970656
In the first question, there are 4 ropes whose upward force holds the 300 kg rope up, and since tension is the same throughout, 300/4 = 75 throughout the whole rope. This means your end pulling down holds 75. Notice that your 75 pointing down plus the 300 pointing down should mean 375 pointing up to counter it. If there were force-measuring spring scales on the top 3 black rectangles, the leftmost would read 75, and the two on the right would read 150 each, so the numbers add right.For the second question, logic is the same. 6 ropes hold the 300 up with equal tension, so overall 300/6 = 50, which means your response should be correct. Tell your teacher if they marked it as wrong and said it was supposed to be 60. Similar to the above, the left rectangle holds 50, the middle two hold 100 each, and your arm on the rightmost side holds 50 up, meaning 300 overall up to counter the 300 block pointing down.
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Anon05/06/26, 03:29No.16970855
that last pulley in problem 3 isn't going to be lifting anything, and the rope would just fall off of it rather than sticking up in the air like that.
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Anon05/06/26, 05:39No.16970881
yes your teacher is retarded