# problem solving

1. ### Comp Sci Counting valleys problem

// Complete the countingValleys function below. // The code is in javaScript function countingValleys(n, s) { let currentLevel = [] // an array of numbers that indicate the number of units of altitude above or below sea level regarding each step let altitude = 0 // the...
2. ### Relative Density Word Problem

So I am a bit stuck on this question as my result using the above equations dose not give an numerical value which I assume from the question is needed. So here my method for solving My first thought was that if on the planet the person can throw a rock 10 time further then that it implies in...
3. ### When can using a logarithm make solving an equation easier?

Homework Statement Well, there is a physics problem I was solving and it is really interesting how it is officially solved. We take a small weight and hang it on a steel wire. For how much does the oscillation time change if the temperature of this wire raises for 10K? I looked up solution...
4. ### Studying Are there any good exercise books for Quantum Mechanics?

hi, I’ve been walking through posts on this forum, and found plenty of book recommendations for QM. My problem is, I haven’t had enough practice in a long while. I could go over Solved Problems in e.g. Galitsky, or Gasiorowitz, but they seem to be a little far from what I want to test...
5. ### Studying Should examples be looked at before solving problems?

So, with introductory level Physics, say Mechanics (Halliday's book or Kleppner and Kolenkow), am I making a mistake by looking at examples after reading, and understanding theory before trying to solve exercise problems? How does this change with advanced undergraduate level/beginning graduate...
6. ### Classical Improving my problem solving skills...

Hi everybody! I've just finished my 4th year of physics degree (1st year of the masters degree, to be more exact) and I feel that I've spent most of my time reading theory and studying proofs and very few time on actual problem solving. In order to change that, I decided this summer go through...
7. ### Other Book recommendations for making guesses, estimates, inferences

I came across this book 'Street fighting Mathematics, The art of educated guessing and opportunistic problem solving' , by Sanjoy Mahaan, published by MIT press. The book talks about how we can guess some property of the solutions of a number of physics and math problems without actually solving...
8. ### Difficuilt and/or interesting problems in fluid mechanics

Homework Statement Can anyone please give me hard and interesting problems regarding fluid mechanics problems such as hydrostatic and air prssure bouyance force and Bernoullis equation(Bernoullis equation problems only for liquids)? I tried looking for them but the ones I found were quite...
9. ### Insights 10 Math Tips to Save Time and Avoid Mistakes - Comments

Greg Bernhardt submitted a new PF Insights post 10 Math Tips to Save Time and Avoid Mistakes Continue reading the Original PF Insights Post.
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### Programs Question about double major

For a long time I wanted to get degrees in both mechanical and electrical engineering and I recently heard about double majors. For me it's not as much about jobs I want in the future. I wanted to become an engineer because they are problem solvers. I wanted to invent things and or make them...
11. ### Schools A college degree for creating the ultimate problem solving mind

I have frequently read and heard that mastering physics is the ultimate way to mold a problem-solving mind. Therefore, becoming a physics major is supposed to be the best way of doing so. I wonder to what degree that statement holds true. Is it true? Is it biased? Am I misinterpreting...
12. ### Light in a cup (Can you explain this phenomenon?)

Can anyone explain the behavior of light I came across as I sat in my lounge this evening having a nice cup of Mocha . Hint ( I am sitting in a room with some led ceiling lights on) can you: 1.Guess how many Led lights I have on 2.Explain the appearance of light which is looking like a typical...
13. ### A Queueing Problem

First post and I'm wondering if I could get some help. I'm new to queueing theory so I'm not sure how to solve this problem. Population-------------> Queue--------------> Server I have a calling population that is infinite or a vast amount. The queue capacity is limited at 13. There is 1...
14. ### B Determine speed of car from result of impact?

Greetings, It's been quite a while since I had to do anything with velocity, friction, mass, and practically any physics over simple calculations. My car was hit yesterday while parked. There were no injuries, and it still drives just fine. The collision was hard enough to deploy the other...
15. ### Two cars moving towards each other - bullets fired

Homework Statement This problem-solving question is about a police car chasing criminals. Two cars are moving in the same direction, parallel (assumed). One car is moving at 82 km/h. The other car is moving at 64 km/h. Bullets are fired from the car moving at 82 km/h towards the car moving at...
16. ### LC Circuit problem help

Homework Statement 4700uF Capacitor is initially charged to 9.0V, then the voltage source is removed and the capacitor is connected across a 1.50H inductor. Solve for: Energy of the Circuit, Imax, and Time after Circuit connected whed Energy of the capacitor =Energy of the inductor Homework...
17. ### Can we solve for x(t) and y(t) with respect to time?

Homework Statement I would like to ask a question I was discussing the other day with a friend of mine. Suppose you have a point mass m, sliding on the friction-free curve y = e^{-x} starting from position x(0) = 0 and y(0) = 1 with zero initial velocity. Can we find in closed-form the exact...
18. ### Prism gains mass due to light!

Homework Statement Figure 1.1 shows an equilateral glass prism illuminated by a 100 W laser beam of wavelength λ = 600 nm. The refractive index of the glass of the prism is 1.50 at λ = 600 nm. The path of the light in the prism is parallel to the base of the prism. The momentum of a photon is...
19. ### Studying Problem solving of complex physics problem

What kind of steps do you use when you need to solve a complex physics problem? What kind of questiono do you ask yourself? Richard Feynman said that you have to write down the problem and then think hard, but what thoughts and questions can help yourself find a creative solution? Is creativity...
20. ### C: Highly prime numbers

Homework Statement Write a program that will print all highly prime numbers from the input interval <a,b>. Prime number is highly prime if deletion of every digit from right is a prime. Example: 239 is highly prime because 239,23,2 are primes. 2. The attempt at a solution Could someone point...
21. ### Understanding the use of a figure in thermodynamics.

I came across an equation used in one of the forums from a few years ago. Found here: https://www.physicsforums.com/threads/calculate-how-long-it-will-take-for-the-ice-to-melt.531908/ I am researching a similar topic into melting ice and using it as a cooling solution. However when i came...
22. ### Having trouble trying to relearn physics

I'm trying to relearn physics the summer. I've been studying some basic calculus and I've enjoyed it. But I'm going back to solving problems that don't involve any calculus, such as kinematics (like using the suvat equations). Now the problem is I'm having a very difficult time solving some...
23. ### Problem Solving Quiz

Here's a fun little quiz to test your problem solving skills. It's something I'd recommend all scientists or aspiring scientists take a shot at, as I learned a lot by taking the quiz: http://www.nytimes.com/interactive/2015/07/03/upshot/a-quick-puzzle-to-test-your-problem-solving.html It's...
24. ### My approach to physics seems pointless.

Greetings. I completed my bachelor's in physics from the 'University of Delhi', India, an year ago and I wish to pursue a career in fundamental research. I knew that a Master's in Physics was a very serious business and thus took an year off making sure i was ready for it. However i have been...
25. ### Optimization methods with bivariate functions

Hi, I have the following equation: f(z)=g(z)+b*u(z) where z=(x,y) i.e. bivariate,b is a parameter, u(z) the uniform distribution and g(z) a function that represents distance. By considering for a momment b=0, min(f(z)) can give me the location of the minimum distance. However because I want...
26. ### Problem solving skills for Physics Olympiad

I am trying to do well in this year's National Physics Olympiad here to qualify for the APhO and IPhO team. So I need to increase my skill of solving physics problems. What books are the best for physics problems and also teaches the problem solving skills??? I am already studying University...