Exercise Definition and 578 Threads

http://onlinelibrary.wiley.com/doi/10.1111/acel.12750/full The effect of lifelong exercise decreases the immune system's degradation with age. Lifelong cyclists were compared to more sedentary age-matched counterparts. Several markers for immune system activity level were found to be higher...

Homework Statement Homework Equations The Attempt at a Solution I'm confused avout questions 2-3. The answers for 2-2 is 1 So the answer for 2-3 is $$\frac{1}{3}$$ But, how the area looks like? Because $$ x^2 $$ will be an open curve upside? There's no boundary for above side.

Homework Statement Homework Equations Conservation of momentum: m1*v1 + m2*v2 = k Conservation of mech. energy 1/2 * m * v^2 + m * g * h = k The Attempt at a Solution Why can't i just use conservation of energy to solve this one? I know that the bullet contains all the kinetic energy before...

Homework Statement Homework Equations F = ma The Attempt at a Solution The gravity pulls on m with a force Fg: Fg = m*g This force is directly translated into pulling the total mass m+M with an acceleration a: (m+M)*a = Fg <=> a = Fg / (m+M) = m*g / (m+M) with this acceleration, we can...

Homework Statement The skier is skiing without friction down the mountain, being all the time in a specified plane. The skier's altitude y(x) is described as a certain defined function of parameter x, which stands for the horizontal distance of the skier from the initial position. The skier is...

I am reading the book: "Discovering Modern Set Theory. I The Basics" (AMS) by Winfried Just and Martin Weese. I am currently focused on Chapter 1 Pairs, Relations and Functions ... and I am in particular focused on Cartesian Products and indexed families of sets ... I need some help with...

Homework Statement Find the expression for c_p - c_v for a van-der-waals gas, with the equation of state \Bigg{(}p+\dfrac{a}{V^2}\Bigg{)}(V-b)=RT Homework EquationsThe Attempt at a Solution Basically I've proved c_p - c_v = \Bigg{[} p + \Bigg{(}\dfrac{\partial E}{\partial V}\Bigg{)}_T...

Homework Statement In Ex. 2.4 from textbook Supergravity by Freedman and Van Proeyen one needs to prove the following identity $$ A^\dagger \sigma_\mu A=\sigma_\nu \Lambda^\nu{}_\mu $$ Homework Equations It is easy to prove the other identity in this exercise $$ A\bar{\sigma}_\mu...

Homework Statement I have a couple of issues with this problem, but first of all, I want to find out what I am missing in my attempt to prove ##∇^2Φ = 4πρ## Homework Equations See below The Attempt at a Solution [/B] If ##Φ = \frac {-M}{r}## Then ##Φ_{,i} = \frac {Mx^i}{r^3}## So ##Φ_{,ii}...

I am reading Houshang H. Sohrab's book: "Basic Real Analysis" (Second Edition). I am focused on Chapter 2: Sequences and Series of Real Numbers ... ... I need help with Exercise 2.1.10 Part (c) ... ... Exercise 2.1.10 Part (c) reads as follows:I am unable to make a meaningful start on...

I am reading Houshang H. Sohrab's book: "Basic Real Analysis" (Second Edition). I am focused on Chapter 2: Sequences and Series of Real Numbers ... ... I need help with Exercise 2.1.10 Part (b) ... ... Exercise 2.1.10 Part (b) reads as follows: I am unable to make a meaningful start on...

Ordering on the Set of Real Numbers ... Sohrab, Exercise 2.1.10 (a) ... I am reading Houshang H. Sohrab's book: "Basic Real Analysis" (Second Edition). I am focused on Chapter 2: Sequences and Series of Real Numbers ... ... I need help with Exercise 2.1.10 Part (a) ... ... Exercise 2.1.10...

I am reading Houshang H. Sohrab's book: "Basic Real Analysis" (Second Edition). I am focused on Chapter 2: Sequences and Series of Real Numbers ... ... I need help with Exercise 2.1.12 Part (1) ... ... Exercise 2.1.12 Part (1) reads as follows: I am unable to make a meaningful start on...

Homework Statement A cell with 16 chromosomes undergoes meiosis. One of the then formed cells (at the end of meiosis 2) gets fertilized by an unknown gamete. The zygote formed from this fertilization undergoes mitosis 3 times. How much DNA-strands will there be at the end, only taking into...

I am reading Houshang H. Sohrab's book: "Basic Real Analysis" (Second Edition). I am focused on Chapter 2: Sequences and Series of Real Numbers ... ... I need help with a part of Exercise 2.2.7 Part (1) ... ... Exercise 2.2.7 Part (1) reads as follows:I have managed a solution to this...

Homework Statement I am reading Houshang H. Sohrab's book: "Basic Real Analysis" (Second Edition). I am focused on Chapter 2: Sequences and Series of Real Numbers ... ... I need help with a part of Exercise 2.2.7 Part (1) ... ... Exercise 2.2.7 Part (1) reads as follows: I have managed a...

I am reading Houshang H. Sohrab's book: "Basic Real Analysis" (Second Edition). I am focused on Chapter 2: Sequences and Series of Real Numbers ... ... I need help with a part of Exercise 2.2.4 Part (3) ... ... Exercise 2.2.4 Part (3) reads as follows: I am unable to make a meaningful...

Homework Statement I am reading Houshang H. Sohrab's book: "Basic Real Analysis" (Second Edition). I am focused on Chapter 2: Sequences and Series of Real Numbers ... ... I need help with a part of Exercise 2.2.4 Part (3) ... ... Exercise 2.2.4 Part (3) reads as follows: Homework...

I am reading Houshang H. Sohrab's book: "Basic Real Analysis" (Second Edition). I am focused on Chapter 2: Sequences and Series of Real Numbers ... ... I need help with a part of Exercise 2.2.4 Part (2) ... ... Exercise 2.2.4 Part (2) reads as...

I am reading Houshang H. Sohrab's book: "Basic Real Analysis" (Second Edition). I am focused on Chapter 2: Sequences and Series of Real Numbers ... ... I need help with Corollary 2.1.39/Exercise 2.1.40 ... Corollary 2.1.39/Exercise 2.1.40 reads as...

I am reading Houshang H. Sohrab's book: "Basic Real Analysis" (Second Edition). I am focused on Chapter 2: Sequences and Series of Real Numbers ... ... I need help with Exercise 2.1.29 ... Exercise 2.1.29 (including the Completeness Axiom) reads as...

I am reading Ethan D. Bloch's book: The Real Numbers and Real Analysis ... I am currently focused on Section 1.5: Constructing the Rational Numbers ... I need help with Exercise 1.5.9 (3) ...Exercise 1.5.9 reads as follows: We are at the point in Bloch's book where he has just...

I am reading Dummit and Foote, Chapter 13 - Field Theory. I am currently studying Section 13.2 : Algebraic Extensions I need some help with Exercise 13 of Section 13.2 ... ... indeed, I have not been able to make a meaningful start on the problem Exercise 13 of Section 13.2 reads as...

Homework Statement I am reading Dummit and Foote, Chapter 13 - Field Theory. I am currently studying Section 13.2 : Algebraic Extensions I need some help with Exercise 13 of Section 13.2 ... ... indeed, I have not been able to make a meaningful start on the problem ... ... As indicated...

I am unsure of my approach to Exercise 2 Dummit and Foote, Section 13.2 : Algebraic Extensions .. I am therefore posting my solution to the part of the exercise dealing with the polynomial g(x) = x^2 + x + 1 and the field F = \mathbb{F}_2 ... ... Can someone please confirm my solution is...

I need help with Exercise 1 of Dummit and Foote, Section 13.2 : Algebraic Extensions .. I have been unable to make a meaningful start on the problem ... ... Exercise 1 of Dummit and Foote, Section 13.2 reads as follows: I have been unable to make a meaningful start on this problem ...BUT ...

Homework Statement I am reading Dummit and Foote, Chapter 13 - Field Theory. I am currently studying Section 13.1 : Basic Theory of Field Extensions I need some help with an aspect of Exercise 1 ... ... Exercise 1 reads as follows: Homework Equations Relevant theorems for this exercise...

I am reading Dummit and Foote, Chapter 13 - Field Theory. I am currently studying Section 13.1 : Basic Theory of Field Extensions I need some help with an aspect of Exercise 1 of Section 13.1 ... ... Exercise 1 reads as follows: My attempt at a solution is as follows:p(x) = x^3 + 9x + 6 is...

<Mentor's note: moved from a technical forum, therefore no template.> I'm long out of college and trying to teach myself QM out of Shankar's. I'm trying to understand the reasoning here because I think that I am missing something... 1.1.3 1) Do functions that vanish at the endpoints x=0 and...

So, in preparation to the Portuguese Astronomy Olympiads, I've stumbled upon this problem (exercise): The sun, which is 8 kpc away from the centre of the Milky Way, has a rotation speed of approximately 220 kms-1 . Whereas a a star that is 15 kpc from the centre of the Galaxy orbits at a speed...

Hello everyone, this is my first post, so go easy on me! Thank you to those who are able to help. 1. Homework Statement The problem is taken from Professor Shankar's Fundamentals of Physics exercises (Problem 3). Romeo is at x = 0 m at t = 0 s when he sees Juliet at x = 6 m Romeo begins...

Based on an incorrect understanding of special relativity a) Pick a problem from a textbook, and come up with a different answer than the textbook does. Additionally, do one or both of the following: b1) Argue that the textbook answer is wrong and you are right b2) Argue that there is an...

Hello :) Help please about the following exercise : The function f(x) comes up and is an convex which gets out from (0,0) and continues into the first quarter. Prove that for all w > 0, takes place f(1 + w) > f(1) + w*f(1). I have been trying for two days to solve it :\ Thanks a lot!

Homework Statement Equation: x^2+y^2-6x-2y+8=0 Find the center and the radius. (Help) : Find the equation of the tangent to the circle above that passes through the beginning of axis O (0,0)The Attempt at a Solution I found the center and radius and i believe the values are : C (3,1) and R...

Homework Statement If G be the centroid of ΔABC and O be any other point, prove that , ## 3(GA^2 + GB^2 + GC^2)=BC^2+CA^2+AB^2## ##and,## ##OA^2 + OB^2 + OC^2 = GA^2.GB^2+GC^2+3GO^2## Homework Equations i m practising from S L LONEY coordinate geometry first chapter ... only the equation...

We all know that there's plenty of evidence showing that exercise does benefit cognition. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3951958/ The real question is how can I actually use this in practice to get real world results. So if I spend 8 hours a day studying a certain subject/trade...

Homework Statement In the drawing you can see a circumference inscribed in the triangle ABC (See the picture in the following link). Calculate the value of X https://goo.gl/photos/CAacV2dJbUrywfXv92. The attempt at a solution It seems I found a solution for this exercise with the help of a...

Hello and I would like to thank you for your space in this website I'm from Greece and i have exams in next days I need some help with an exercise that I can not solve! There is a probability density function with the following type : P(Y=y/X=x)=f(y,x)= {n \choose y}* {x}^{y} *...

Knowing Ks=6⋅10−38 for Fe(OH)3 in neutral solutions, calculate the minimum pH of an acidic solution in order to completely dissolve 10 mg of Fe(OH)3. Data: Volume = 0.1 L. I set out the equation for the equilibrium constant. having first calculated the concentration or iron ions (9.35899*10-4...

Homework Statement Given 2 int arrays, a and b, of any length, return a new array with the first element of each array. If either array is length 0, ignore that array. front11([1, 2, 3], [7, 9, 8]) → [1, 7] front11([1], [2]) → [1, 2] front11([1, 7], []) → [1] Homework EquationsThe Attempt at...

Homework Statement In an visual binary star system,the apparent magnitude of the primary star is m=9.8 and its spectrral type is G2V.The angular semi-major axis is φ=0''.1 and the period of the system is 24y.Find the distance of the system r and the two masses.The Sun's absolute magnitude is...

Homework Statement A disturbance signal propagates in a ventilation duct with cross-sectional area A=0,04m2. The fundamental frequency of the disturbance signal is 250Hz and its spectrum consists of odd harmonics only. Choose the appropriate filter options for rejecting this particular...

Homework Statement Proof the leptonic-hadronic tensor multiplication, with ##p^\mu=(M,\textbf{0})## and ##p'^\mu=(E',\textbf{p}')## is rest target and final target momentum respectively, and ##k^\mu=(\omega,\textbf{k})##, ##k'\mu=(\omega' ,\textbf{k}')## is momenta of incoming and outgoing...

Hello! My professor distributed this problem as a practice exercise but I'm not sure how to go about it. Can someone point me in the right direction? Thank You!

Homework Statement A mass ##m_1## is attached to a second mass ##m_2 > m_1## by an Acme (massless, unstretchable) string. ##m_1## sits on a frictionless inclined plane at an angle ##\theta## with the horizontal; ##m_2## is hanging over the high end of the plane, suspended by the taut string...

Homework Statement A mass ##m_1## is attached to a second mass ##m_2## by an Acme (massless, unstretchable) string. ##m_1## sits on a frictionless table; ##m_2## is hanging over the ends of a table, suspended by the taut string from an Acme (frictionless, massless) pulley. At time ##t = 0##...

Hi, I'm training an advanced calisthenics exercise called the planche. And I noticed a while ago that doing it with my legs apart (this is called "straddle planche") it's noticeably easier than if I put my legs together (this is called "full planche"). In fact the first is used as a transition...

Hello PF, I have heard many times and read in many places that good exercise for at least half an hour a day can be a booster to cognitive functions and helps with studying. And my university campus is huge so everyday just getting from one place to another stackes up into a 12000 steps a day of...

Homework Statement We're driving with a Uav of 80 km/h The duration Δt is 2 h 45 min On a rainy day, our Uav' is 65 km/h If the distance is the same, how much more is the duration of the drive? So, technically we want the result of Dt = Δt' - Δt Homework Equations Uav = Δx / Δt The Attempt at...

I am having a very difficult time comprehending this exercise and any direction would be appreciated. Feel completely lost! Not necessarily asking for the answer just want to know how to tackle this. This program will output a right triangle based on user specified height triangleHeight and...