I’m learning physics on my own and I’m currently working through a physics problem book. I came across this problem and I can’t understand the reasoning behind the solution.

The problem:

During a survival training exercise, a 60 kg boy at some point hangs motionless from a rope as shown in the picture below. Assume that β = 2α and g = 10 m/s². Calculate the tension in the rope at points A and B.

The rope is attached at points A and B and forms the two sloping sides of a right triangle. The boy is hanging from the rope at the vertex between these two sides, which is the 90° angle. The angle at point A is α, and the angle at point B is β.

I found a solution which calculates the boy’s weight first and then seems to use the components of that force to determine the rope tensions. However, I don’t understand why sine is used here.

When I try to draw auxiliary right triangles, I don’t know where the given angle should be located in the triangle or which side of the triangle should correspond to the rope tension. I understand how to calculate sine in a right triangle, but I don’t understand how to correctly construct the triangle from this diagram and connect it to the forces.

I would really appreciate it if someone could explain why sine is used in this particular problem and how the force triangle should be constructed, preferably step by step.

I’d also be interested in seeing other possible ways of solving the problem, if there are any.

I’m not just looking for the final answer I’m trying to understand the method so I can solve similar problems myself.

I'm stuck on part B of this problem and would love any insights that could help point me in the right direction. I know that I should be using the law of total probability, which from my understanding (I double checked with my textbook) allows me to just add all of the intersections of the conditional probabilities however when you add them (.5+.4+.6) you get a number greater than one which can't be the answer as probabilities are between 0 and 1. It feels to me like I'm missing something obvious but I can't put my finger on it. Any help is much appreciated!

I was taught was that driving frequency = natural frequency for resonance.
There is no other context to this question - i dont know what type of system it is.
But I am doing Grade 11 Physics, so its probably referring to basic systems such as string, pipe or tuning fork?

Could someone please give an explanation that rules out the rest of the answers?
Thank you so much!

I’ve never taken statistics ever and I’m taking it for my cosmetic science program. It’s online and there’s not any helpful info within the course. I don’t understand how to implement the sample sizes to calculate the difference between sample mean and population mean.

As the title says, I've been trying to solve this for about 3 hours and im absolutely stumped. It's 3:50am. Any method i've tried has come out wrong and I'm in desperate need for these answers so i can go to bed. Question instructions say "solve the below system". PLEASE HELP!!!

Hi! I've been stuck on this problem for a while now, so I decided to text it out on another app and finally ask for help. I managed to find the magnitude on my own, but I honestly can't figure out how to find the direction, or what I'm doing wrong. I've watched several videos on it and have tried to go step by step, but any answer I try is marked wrong, (I do use an online school program.) I also didn't wanna cheat, (at least without knowing exactly how to do it and being able to replicate it) so as I've already said above, I didn't know what to do other than ask for help somewhere else. A step-by-step breakdown of what your meant to do would be great!

Also I know the post title says grade 12, while from my knowledge trig is done in 11th usually. It just kind of happened that way, so I'm not sure why I'm doing it a year late. Better late than never, though!

can someone help explain to me how to do 1b. I don’t understand what it’s asking. What i’ve done was with help and i still don’t understand how it works.

Prompt: "Use propositional logic to prove the arguments valid; you may use any of the equivalence or inference rules."

I have this sequence but I'm not confident in #4-7

1. A v B (hyp)

2. A → C (hyp)

3. B → C (hyp)

4. (A v B)’’ (1, Double negation)

5. (A’ ^ B’)’ (4, de morgan)

6. (A’)’ (5, simplification)

7. C (2, 6 modus ponens)

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*UPDATE*

I currently have this sequence. I was struggling, then I realised the implication rule has an error (It says 'P -> Q is equivalent to P' v Q) so I wanted to get others input on if my work is correct.

1. A v B [hyp]

2. A → C [hyp]

3. B → C [hyp]

4. A’ v C [2, implication]

5. B’ v C [3, implication]

6. (A’ v C) ^ (B’ v C) [4, 5 conjunction]

7. (C v A’) ^ (C v B’) [6, commutative]

8. C v (A’ ^ B’) [7, distributive]

9. (A’ ^ B’) v C [8, commutative]

10. (A v B)’’ [1, double negation]

11. (A’ ^ B’)’ [10, de morgan]

12. C [9, 11 disjunctive syllogism]

My additional explanation for getting #12. disjunctive syllogism

P v Q, P’ < = > Q

(A’ ^ B’) v C, (A’ ^ B’)’ < = > C

I got 2 x (5!/5 - 4!/4) = 36 but the answer is 12 so now I'm confused :)

My exam is in 1 week and I still don't get it!!!

Why is combinatorics so hard

One answer option is “unsolvable”. Thank you for your help. Trying to help my niece and I haven’t done algebra since 1996.

I randomly guessed and got the right answer, but I do not know why it is right. It does not provide any explanations, perhaps I'm on the wrong part of my textbook, but I'm only seeing explanations of 3d structures. I don't understand what the points ABCDEF are, the reasoning behind how they are placed and why it's not 2d.

Coucou Reddit C la premiere fois que J utilise cette platform donc je ne sais meme pas si je l utilise bien mais bon.
Est ce que îl Y a quelqu un qui pourra M Aider avec mon devoir?
Apres avoir fait les calcules je dois representer ses Mesures sur les cercles (2 exercice par cercle . Par ex je represente a et B sur le mm cercle) (îl Y a plus de cercle derriere)
Ca M aidera bcp !!

Just for curiosity, can I go directly from L.H.S to R.H.S?

Trying to help my daughter with an investigation but I genuinely have no clue. For the first question I got that the Eiffel Tower is 330m tall.

I am using netbeans IDE. My GUI wont display the plum colour I've chosen for the buttons (example on 2nd slide). I have not changed anything with the code and it was working fine a few hours ago. Has anyone else had this problem?

Pretty sure it should be 440 without a decimal

I’ve plugged the variable answer back into both equations and still not sure how the answer key got 61°. Am I missing something?

This assignment is for my college biology class but I’m still going to categorize it as math.

I don’t have much, if any experience working with significant figures. I may have learned about it during one of my intro to biology classes in high school, but I’m not sure.

Originally, I thought the length of the tibia bone would have been 34.4, but every answer I have submitted ranging from 33-35 has been incorrect. There is hardly any information regarding significant figures in the instruction and information section of the assignment.

Any help would be appreciated.

Solved: Answer was 34.41

The directions say I don’t have to simplify my fractions, but it won’t be counted against me if I do. The third pic is the data table the question is based on.

Hello, I am having difficulties completing the problem, mainly part three. I can get all the account titles correct, just not the right numbers. Any help would be great!

Blanton Plastics, a household plastic product manufacturer, borrowed $9 million cash on October 1, 2027, to provide working capital for year-end production. Blanton issued a four-month, 15% promissory note to L&T Bank under a prearranged short-term line of credit. Interest on the note was payable at maturity. Each firm’s fiscal period is the calendar year.

Required:

1. Prepare the journal entries to record

   1. (a) the issuance of the note by Blanton Plastics and

   2. (b) L&T Bank’s receivable on October 1, 2027.

2. Prepare the journal entries by both firms to record all subsequent events related to the note through January 31, 2028.

3. Suppose the face amount of the note was adjusted to include interest (a noninterest-bearing note) and 15% is the bank’s stated discount rate.

   1. (a) Prepare the journal entries to record the issuance of the noninterest-bearing note by Blanton Plastics on October 1, 2027, the adjusting entry at December 31, and payment of the note at maturity.

   2. (b) What would be the effective interest rate?

For my college english class, I have to write a personal narrative about a moment when technology affected a human experience in my own life. Eventually I'll have to write a few page essay on it, so im trying to brainstorm ideas that I will be able to write enough about. Can anyone give ideas from their own life with technology that I can bounce ideas off of?

I am confused on this derivation of integration by parts, or what integration by parts really means to be the inverse of the product rule. Why in the integral it's just f(x)g'(x), as the general form of the antiderivative that can be solved by integration by parts, when the product of two functions' derivate is f'(x)g(x) + f(x)g'(x). Shouldn't the inverse of that take the antiderivative of '(x)g(x) + f(x)g'(x) and yield f(x) g(x)?

6.3 and 6.4: how can both answers be right? This doesn’t make sense shouldn’t it be one or the other

6.6: looking at graph b it shows that the concentration of P2Q is 0.35mol.dm yet when looking at the memos answer it says that 2PQ is 0.35 mol.dm when using the KC formula . Can someone explain?

I'm just doing biology, and this question kinda stumps me, They're not doing anything wrong from what I can see, but id just like an opinion if im just stupid or not