# What is Irodov: Definition and 46 Discussions

Igor Yevgenyevich Irodov (Russian: Игорь Евгеньевич Иродов; 16 November 1923 – 21 October 2002) was a Soviet Russian physicist and World War II veteran. He was mostly known as a physics professor at the Moscow Institute of Physics and Engineering (MEPHi) and the author of a series of handbooks on general physics, which became lecture courses in physics in several countries.

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1. ### Oscillations in an LC circuit (Question from Irodov)

https://www.physicsforums.com/attachments/282131
2. ### Classical Irodov or Krotov for high schoolers?

How far you recommend krotov to high schoolers? like i genuinely want to improve my problem solving skills as i have given enough time in concepts and derivation stuffs...even of non routine courses but yeah need to sacrifice a few things for irodov! so?
3. ### Irodov: Tape going down a ramp

Hello everbody, I found the following resolution: We can consider the winding of the wire as a thin disc. Like this, For a given instant t, we will have M (t) mass of the disc and R (t) radius of the disc. Analyzing linear dynamics: $$M(t)gsen\theta - T = M(t).a$$ Analyzing the...
4. ### (I.E. Irodov problem 1.72) Dynamics problem involving a pulley

. First thing that I notice is that the other part of string (to which body 2 is connected) is fixed. Therefore, I concluded that the body 2 is stationary with respect to the pulley 2 (let's agree that pulley to which body 1 is connected is pulley 1 and in same way pulley 2 is defined)...
5. E

### Chemistry Equivalent of Irodov for Chemistry?

I need to brush up on some Chemistry over Summer, and I wondered if anyone knew of some problem books pitched at a similar level to Irodov's problem book for Physics, or things like IChO questions. Preferably it would include all of physical, inorganic and organic, to some degree. I get various...
6. ### I.E. Irodov Problems in General Physics, 1.304

My struggle here comes from finding the bending moment ##N(x)##. My working is as follows. We want to find the bending moment on an element a distance ##x## away from the axis of rotation. To do so, let us consider the bending moment due to the force on an element ##\xi>x## away from the axis...
7. ### Irodov problem 1.12 — A 3-body gravitational attraction problem

The thing is, I've already looked up at the solution online at it's t= 2a/3v. But I've approached it a different way and I can't really tell what I'm doing wrong, my solutions gives out t= (a/√3v )* (π/3),I don't know what's wrong with it. Here's my approach: The points will meet at the...
8. ### Charge induced on parallel plates if a charge between plates

Two infinite conducting plates 1 and 2 are separated by a distance l. A point charge q is located between the plates at a distance x from plate 1. Find the charges induced on each plate. Many of the places this problem has been solved by considering an infinitely large plate in place of the...
9. ### Help with an Irodov problem (Problem 3.3 electrodynamics )

Homework Statement Two small equally charged spheres, each of mass m, are suspended from the same point by silk threads of length 1. The distance between the spheres x << 1. Find the rate dqldt with which the charge leaks off each sphere if their approach velocity v = a/ √x, where a is a...
10. ### What mistake did I make in finding the net force on a rotating disc?

Homework Statement A horizontal disc is rotating with an angular velocity w about its axis perpendicular to its plane. A small body of mass m moves with velocity v relative to the disc alog the diameter. Find the net force exerted by the disk on the body as function of radius from centre...
11. ### Classical Book for thermodynamics at undergrad level

I want to solve Irodov's problems in thermodynamics and for this I need a good textbook. I have Heat and Thermofynamics, Dittman and Zemansky. Should I read this book or should I go for another book?
12. ### Maximum distance the car accelerates in a circle without skidding

Homework Statement Homework EquationsThe Attempt at a Solution At distance s, the speed of the car is v. $$v^2 = 2wτs$$ $$\frac { mv^2} R ≤ kmg$$ Let's denote the maximum distance covered without sliding is smax. $$\frac { m2wτsmax} R = kmg$$ $$smax = \frac {kgR} {2wτ}$$ Is this correct...
13. ### Projectile motion, radii of trajectory

Homework Statement Homework EquationsThe Attempt at a Solution For part (d), The curvature radius of trajectory at its 1) initial point = horizontal range/2 =( v02 sin (2α))/2g 2) peak = height of ascent/2 = ( v0 sinα)2 /2g Is this correct? In this problem, the time of ascent is equal...
14. ### Calculating distance, angle bet. velocity and acceleration

Homework Statement Homework EquationsThe Attempt at a Solution A) [/B] s = √[(x2) + (y2 ) ]= a√[2(1- cos (ωt) ) ]|t= Γ The book says, s = aωΓ What I can do is , For very small Γ i.e. ωΓ<<1 , cos (ωΓ) ≈ 1 - {(ωΓ)2}/2 Then , I get, s = aωΓBut, in question it is not given that ωΓ<<1. So...
15. ### Difference: mean velocity & modulus of mean velocity vector

Homework Statement Homework EquationsThe Attempt at a Solution [/B] A) Mean velocity is defined as <v> = total distance traveled/ total time taken = πR/Γ = 0.5 m/s B) How is part a) different from part b)? I think what Irodov means by mean velocity is mean speed in part a. It is mean...
16. ### Calculating the distance to turn off the highway

Homework Statement Homework EquationsThe Attempt at a Solution Speed on a highway = v Speed in the field = η v, is this what is meant by η times smaller? Let's denote CD by x. Now, time taken is t = (AD - x )/v + {√(x2 + l2)}/ ηv For time to be extreme, dt/dx = 0 -1/v + (1/ η v...
17. ### Calculating a bolt's free fall time in an accelerating elevator

Homework Statement Homework EquationsThe Attempt at a Solution A) W.r.t. Earth's frame, After 2s , velocity of bolt = at = 1.2*2 = 2.4 m/s distance traveled = (1/2) 1.2*22 = 2.4 m Let's say that the bolt reaches the floor at time t. Using s = ut + (1/2)at2 2.4 = 2.4t +(1/2)(-9.8) t2...
18. ### Distance between two events w.r.t. two frames

Homework Statement Homework EquationsThe Attempt at a Solution Distance between events w.r.t. Earth frame, De = | (1/2)w(t+Γ)2 - 350 - (1/2)wt2 | = 242 m Distance between events w.r.t. train frame, Dt =350 m , correct? As w.r.t. train frame , the train is not moving. But, a person on...
19. ### Three points at the vertices of equilateral triangle

Homework Statement Homework EquationsThe Attempt at a Solution The direction of motion of all the three particles are changing w.r.t. lab frame. But , their relative velocity remains constant. relative velocity = vb - va And the distance between the two particles decreases from a to 0. So...
20. ### Question about a Conical Pendulum

Homework Statement A conical Pendulum, a uniform, thin rod of mass m and length l, rotates about a vertical axis with angular velocity omega. Find the angle between the vertical and the rod. Homework EquationsThe Attempt at a Solution I know the usual approach to solve this question, write the...
21. ### Capacitor problem from Irodov (3.122)

Homework Statement What charges will flow after shorting of the switch (Sw) in the circuit below through sections 1 and 2 in the direction indicated by the arrows? Homework Equations Kirchoff's laws The Attempt at a Solution Initially, both capacitors will have a charge of...
22. ### Is irodov chapter on light the level of Ipho?

Hi,I am new to this website and this is my first question. I just wanted to ask if irodov's chapter on light is of Ipho level or is it beyond that(that is it for 2nd or 3rd year undergrads) and Aldo what about modern physics. I would have no problem with that but if that is true then I will...
23. ### Calculus IE Irodov equivalent for Maths?

Hello there friends, I'm new here. I'm in my second semester of Computer Science Engineering. I've always loved Maths but was never quite great in Physics in school. I Keep getting this feeling that the current books I'm using aren't delivering the sufficient depth (BS Grewal and Erwin...
24. ### Math level to solve Irodov Problems in General Physics

Greetings, PF. With many recommendations and just enough confidence in my ability to solve problems, I've recently purchased the renowned Problems in General Physics by I. E. Irodov. With excitement, I opened the book and read the first problem. It took a lot of thinking to solve the first few...
25. ### Problems in General Physics by Irodov

Author: I.E. Irodov Title: Problems in General Physics Amazon Link: https://www.amazon.com/dp/8183552153/?tag=pfamazon01-20
26. ### How good is IE IRODOV for physics olympiad

Iam currently preparing for physics olympiad 2014 and i am using IE IRODOV as a problem book. i want to know whether its enough for ipho or should i buy some other book.i have solved about 150 problems from IE IRODOV.
27. ### How Does the Concentration Ratio of Nitrogen to Hydrogen Change with Altitude?

I was trying to solve a problem from Irodov book that asked how the concentration ratio of nytrogen and hydrogen varies with the altitude (initial ratio = n0), considering the temperature to be constant. If there was only one gas, http://img543.imageshack.us/img543/664/77110068.png dP =...
28. ### Convergence Time of Moving Points on an Equilateral Triangle

Homework Statement Three points are located at the vertices of an equilateral triangle whose sides equals a. They all start moving simultaneously with velocity v constant in modulus, with the first point heading continually for the second, the second for the third, and the third for the first...
29. ### Irodov Equilateral Triangle Problem

Homework Statement Hello, so I'm going to be a freshman physics major next year, and over the summer I'm trying to improve my problem solving skills. I've started going through Irodov's problems in general physics, and I have a question about two different solutions to one of the problems...
30. ### I.E Irodov Problems in Physics

How tough is that book?I have heard a lot about it from my friends.They say it has the toughest physics problems.Is it really that tough?I've seen that book,looks scary but have never opened it because I fear I won't be able to solve them and I will get humiliated in front of others.I am...
31. ### How Is Force Calculated to Move Connected Masses on a Frictional Surface?

two masses, m1 and m2 are connected with an undeformed light spring and lie on a surface. the coefficents of friction between the masses and the surface are k1 and k2, respectively. What is the minimum constant force F, that needs to be applied in the horizontal direction to the m1, to shift the...
32. ### Solving Irodov Electrodynamics Homework: Work Required to Transfer Charge q

Homework Statement A point charge q is located at the centre O of a spherical uncharged conducting layer provided witha small orifice as shown in figure. The inside and outside radii of the layer are equal to a and b resp. What amount of work has to be performed to slowly transfer a charge q...
33. ### Solved Physics Problem Book I.E. IRODOV: Q1.315 - Velocity at Point 2

has anyone solved physics problems book I.E IRODOV? i have a doubt in it. question number 1.315, page number 62. can anyone tell me why velocity at point 2 will be greater than velocity at point 1?
34. ### I.E. Irodov Advanced Gravitation Problem

Homework Statement An artificial satellite of mass m of a planet of mass M, revolves in a circular orbit whose radius is n times the radius R of the planet. In the process of motion, the satellite experiences a slight resistance due to cosmic dust. Assuming the resistive force on satellite...
35. ### Uncovering the Life of Mr. IE Irodov

I have been solving problems from the famous book, "IE Irodov" for couple of days..It was really a terrific job for Mr.Irodov to compile such a huge set of wonderful problems which are very much inspirational. I want to know about Mr. IE Irodov.. I have tried wikipedia.org and google as...
36. ### Irodov Problems: Pre-requisites & Suggestions

Irodov problems?? Hi all, I have completed my engineering degree in E&C but now i want to switch my career path to physics. So i was referring "University Physics" by young and Freedman. I have solved all the worked examples and all the Exercise Problems at the end of the chapter of...
37. ### Irodov 1.1 Relative Velocity

1.1. A motorboat going downstream overcame a raft at point A; T=60 minutes later it turned back and after some time passed the raft at a distance l=6.0 km from the point A. Find the flow velocity assuming the duty of the engine to be constant...
38. ### Irodov Physics Questions: General Physics Problems

http://alien.dowling.edu/~rohit/wiki/index.php?title=Problems_in_General_Physics%2C_I.E.Irodov"
39. ### Special Relativity Problem (1.364, Irodov)

Homework Statement The rod AB oriented parallel to the x' axis of the reference frame K' moves in this frame with a velocity v' along it's y' axis. In its turn, the frame K' moves with a velocity V relative to the frame K as shown in Figure. Find the angle (theta) between the rod and the...
40. ### Question from Problems in General Physics (Irodov)

Hi Following is a question from "Problems in General Physics - Irodov". I think I should be able to solve this problem but I don't get a part of the question. Wondering if somebody can clarify what does " velocity which is n=2 times less than the river flow velocity" means is mathematical...
41. ### Irodov Homework Help: Potential of Fields of Force

I've got a problem from Irodov. There are two stationary fields of force F=ayi and F = axi + byj, where i and j are unit vectors of the x and y axes, and a and b are constants. Find out whether these fields are potential. But how do I know that a field is potential? I've read that I have to...
42. ### Does Problems in General Physics by irodov come with solutions?

Does "Problems in General Physics" by irodov come with solutions? Sorry i had to make another thread instead of stick with the first irodov thread on this page, but i need to know if the book provides solutions (or atleast answers) to the problems as soon as possible. This is mostly because...
43. ### Force Acting on Charge on Metal Ball: Irodov Problem 3.69

A metal ball or radius R=1.5[cm] has a charge q=10e-6[C]. Find the modulus of the vector of the resultant force acting on a charge located on one half of the ball. I found a solution on http://irodov.nm.ru/3/resh/3_69.gif but I don't understand explanations regardind to the problem so I would...
44. ### Free Physics Textbooks & Problems: Including Irodov

Big question: where can I find some free physics textbooks and problems. For exemple Irodov?
45. ### Irodov Problems in General Physics

Hey I purchased this book and was wondering how hard do you think this book is?
46. ### Irodov: Best Problems in Physics

Hi all In this forum, I couldn't see a discussion on I.E. Irodov's " Probem in General Physics". I used this book as an undergrad and found it immensely useful. The standard of the problems in extremely good and thought provoking. Problems range from single concept problems to complex...