Homework Definition and 998 Threads

I really need help with a big Python program. Our professor has been MIA for the whole term and now we need to submit a program. I thought I was doing and learning fine on my own, but the program simply does not work for me. I need it till Thursday and I am ripping my hair out because I cannot...

Homework Statement I am studying the topics listed above and have been having great difficulty getting my problems going. To explain, I am having difficulty seeing where the problem should go and attacking in that direction. I can draw out free-body diagrams but I can't see how to solve the...

Homework Statement The problem is this: A car is evenly slowing down from 30 km/h to 0 in the time of 2 seconds. Radius of its wheels is 30 cm. What is its angular acceleration and what total angle will the wheel describe until it stops? How many turns does the wheel make and what is the length...

Homework Statement (a) What shows the existence of shell structure? What are the other numbers? (b) Deduce the spin and parities. Homework EquationsThe Attempt at a Solution The shell model is given by: So for Li, 3 protons pair up with 3 neutrons, leaving an unpaired neutron in...

< Mentor Note -- thread moved to HH from the technical math forums, so no HH Template is shown > Hi, I have already delivered the homework so my reason for asking is because I want to/ need to understand it. I am at question d. I have found the two differential equations. They are: c° =...

Homework Statement Find the Fourier Coefficients for the triangular wave equation shown in this picture: Homework Equations ##f(t)= a_0 + \sum_{n=1}^\infty a_{n}cos(n{\omega}t) + \sum_{n=1}^\infty b_{n}sin(n{\omega}t)## ##a_0 = \frac{1}{\tau}\int_{-\tau/2}^{\tau/2} f(t) \, dt## ## \omega =...

MODERATOR NOTE: MISPLACED HOMEWORK, SO NO TEMPLATE When filling up the tub for a bath, only the hot water tap was turned on. After realizing the mistake after a minute with half the tub at 60 C, how much cold water (as fraction of the whole tub) at 9 C must be added such that the final...

Homework Statement Combustion of hydrocarbon X in excess oxygen produces 0.66g of carbon dioxide, and 0.27 g of water. At room tempertaure and pressure , X is a gas with density 1.75gdm^-3 . What could the molecular of X be? What is the ans ? i only managed to get the empirical formula is CH2...

Hi! Another Physics homework question that needs solving immediately! Thank you in advance. A computer base unit of mass 7.5 kg is dragged along a smooth desk. If the normal contact force is 23 N and the tension in the arm of the person dragging it acts at 23° to the horizontal, then what is...

Homework Statement Attached below Homework Equations E = [kq/r^2]r -------> r is the unit vector The Attempt at a Solution I did the same thing as the solution below, however, I do not understand why there is root-2 in the denominator. I would appreciate it if someone could explain this to me.

Edit: Please see first reply! Hey all! I'm doing my physics homework (online) and think I may have run into an issue. I suspect that the key by which the homework engine grades the problems may be incorrect. Now - I realize this is the Calculus+ section of the Homework section, but my...

Homework Statement An aqueous effluent contains 12 M Cd2+ and 10 M Mg2+ as solution of nitrates. Current practice is use NaOH to selectively precipitate the metals. (a) Is it feasible to get 0 Cd impurities in Mg ppt by using NaF instead of NaOH (back up your answer with adequate calculations)...

I'm currently studying Mechanical Engineering at Level 3 in the UK and I'm beginning my integrated masters in September. I've missed a large chunk of my studies this year due to a broken collarbone I sustained earlier in the year. Instead of getting any special dispensation I'm trying to work my...

1. Homework Statement Homework EquationsThe Attempt at a Solution

Homework Statement See the attached sheet, I had missed todays class due to dentist and I found out we had an assignment due today by end of day, I am having trouble learning this on my own, I am trying right now. Could anyone help me with the solutions? Homework Equations Question one is...

Homework Statement A light string has its ends tied to two walls separated by a distance equal to five-ninths the length of the string as shown in the figure. A 67 kg mass is suspended from the center of the string, applying a tension in the string. What is the tension in the two strings of...

Homework Statement I have attached a screenshot of the question. I know how to use Fourier's theorem for one function but have no idea how to attempt it with a discontinuous function like this. I tried working out a0 by integrating both functions with the limits shown, adding them and...

Homework Statement The new earth-Pluto SuperShuttle line boast that it can take you between the two planets (which are about 5.0 h apart in distance) in 2.5 h according to your watch on board the shuttle. Assume that the shuttle travels at a constant velocity. a.) What time interval must the...

Homework Statement Why does ## \frac{ e^+ + e^- \rightarrow \mu^+ + \mu^- }{e^+ + e^- \rightarrow \tau^+ + \tau^- } \rightarrow 1## at high energies? Would it be the same if it was ## \frac{ e^+ + e^- \rightarrow \mu^+ + \mu^- }{e^+ + e^- \rightarrow e^+ + e^- }##? Homework EquationsThe...

Homework Statement (a) e- + e+ -> e- + e+ (b) e- + e- -> e- + e- c) e- + e- -> e- + e- + u+ + u- d) y -> e+ + e- e) y + y -> y + y Homework EquationsThe Attempt at a Solution Part (a)[/B] Part (b) Part (c) Part (d) Part (e) Not sure what to do with this, since usually the...

Homework Statement I have an upcoming assignment for a Statistics/Probability class that requires me to write a program in R. The assignment requires me to do the following: 1. Obtain the sample mean x and sample variance s2 of the sunspots data. 2. Provide a histogram of the data. 3. For...

Homework Statement Is the equation (x2sinx + 4y) dx + x dy=0 linear This problem also asks me to solve it, but I don't have a problem with that part. Homework Equations An equation is linear if the function or its derivative are only raised to the first power and not multiplied by each other...

First, let me say that I am a senior physics undergrad. I have failed Linear Algebra once before. Otherwise I am a straight A student. I'm also taking Ordinary Differential Equations right now, and I breeze through that class without a care in the world. I'm not sure if I've developed some sort...

Homework Statement Attached Homework Equations The one given in the hint (as attached) for voltage across capacitor wrt time. P=V^2/R The Attempt at a Solution I just wanted to know whether I've gone about this question in the right way. For the first part I simply rearranged the voltage...

Homework Statement A man with mass m1 = 55 kg stands at the left end of a uniform boat with mass m2 = 175 kg and a length L = 2.7 m. Let the origin of our coordinate system be the man’s original location as shown in the drawing. Assume there is no friction or drag between the boat and water...

Homework Statement [/B] Two rocks collide in outer space. Before the collision, one rock had mass 14 kg and velocity ‹4450, −2950, 2250› m/s. The other rock had mass 7 kg and velocity ‹−600, 1900,3600› m/s. A 1 kg chunk of the first rock breaks off and sticks to the second rock. After the...

Homework Statement My professor wants us to program on Python, where we have a certain sequence, for example: sequence = ("one", "two", "three", "four") I need to replace one of the sequence elements (example: "one") with another element (example: instead of the word "one", I need to put...

Homework Statement a) Two astronauts, A of total mass 90kg and B of total mass 110kg are tied together by a light rope 15m long during a space walk. A starts to reel in the rope at her end. After 8.5s she has reduced the length of the rope by 5.5m. What distance does the centre of mass move in...

I am supposed to write a 1 page essay on the origin of friction. I simply do not understand the question. I tried looking up an explanation but I didn't find any thing that I understood. If anyone could explain this to me I would greatly appreciate it!

Homework Statement If you were to throw a large log over the edge of the Grand Canyon and it took 5.65 seconds to hit the ground, calculate the velocity of the log at impact in m/s and calculate the distance the log fell in feet. Homework Equations vf=vi + at, s=d/tThe Attempt at a Solution...

Homework Statement "To illustrate this principle, consider a plane flying amidst a tailwind. A tailwind is merely a wind that approaches the plane from behind, thus increasing its resulting velocity. If the plane is traveling at a velocity of 100 km/hr with respect to the air, and if the wind...

Homework Statement (3xy^2+4y)dx+(3x^2y+4x)dy=0Homework Equations The Attempt at a Solution So First I checked if both equations were exact. I took the derivative of 3xy^2+4y and also derivative of the other and they were both equal so the equation is exact. I took the 3xy^2+4y and integrated...

Homework Statement At an altitude of 50 km, the average atmospheric temperature is 0C. what is the average number of air molecules per cm^3 of air at this atmosphere? Given formula: P(sub h) = P(sub 0) x e^(-Mgh/RT) = -(Mgh x 10^5)/2.303RT Assuming P = 1 atm at sea level and h in km...

Homework Statement This problem is from WileyPLUS. I've been looking through my book, but none of the methods they present work for me. I guess I just don't know how to use them properly. Determine the moments of the 5.6-kN force about the point O and about point B. Homework Equations I...

I need help with my dynamics homework. This is what I have so far, I hope you can read my writing (let me know if something is unclear). Can someone help me with how to approach this problem and where to go next? Thank you!

Homework Statement Find the angle that makes with the positive x axis: (Consider vectors above the x-axis to make positive angles and vectors below the x-axis to make negative angles.) Homework Equations pheta = arctan (Ex/Ey) tan(pheta) = Ex/Ey The Attempt at a Solution I already found that...

I was recently doing a few projectile motion equations and noticed that the formula used changes depending on whether or not a given initial position. Am I correct, or am I misinterpreting the situation and manipulation of the equation? Also, can someone provide a file or pdf for all the...

PLEASE HELP A 68 kg acrobat jumps from a 2 meter ledge on to a trampoline. If the acrobat bounces off the trampoline with a velocity of 10.6 m/s over a contact time of 1.02 seconds, what force did the trampoline exert on the acrobat?Well I ve tried to do it multiples times, using the formula...

Homework Statement (see picture) I understand one approach to this homework problem. I don't understand why an alternative approach fails. Homework Equations V = E*d The Attempt at a Solution The correct answer is (d), zero. An acceptable approach: 1) Realize that V is the same at both...

Homework Statement A speaker emitting sound at a frequency of 20 Hz is moving in the +x direction between two detectors. The speaker is moving at a speed of 30 m/s and the detectors are wired so that they flash red (λ = 700 nm) when the pressure is a maximum and green (λ = 700 nm) when the...

Homework Statement What are the fundamental frequencies for a 50 kHz square waveform of 50% duty cycle and a 25 kHz sinusoidal waveform, respectively? (The duty cycle of a square waveform is the ratio between the pulse duration and the pulse period.) Homework Equations My teacher then gave...

The problem is: A 230-m-wide river has a uniform flow speed of 1.4 m/s through a jungle and toward the east. An explorer wishes to leave a small clearing on the south bank and cross the river in a powerboat that moves at a constant speed of 4.6 m/s with respect to the water. There is a clearing...

Ok let me just type the question and get to the real question I have. If you traveled one mile at a speed of 100 miles per hour and another mile at a speed of 1 mile per hour, your average speed would not be (100 mph+ 1 mph)/2 or 50.5 mph. What would be your average speed? (Hint:what is the...

I was asked to prove that any function u(z,t)=f(z-vt) is a solution of the wave equation ∂2u/ dt2= v2 · ∂2u/dz2 I know that v is constant and z and t are independent. I've tried looking at Lorentz law but I am getting nowhere fast. Please help!

Homework Statement Uploaded for viewing Homework EquationsThe Attempt at a Solution I tried using the acceleration, ax, and the distance, 9m, to find the time. THen, since speed = d/(delta)t, I got 2.12 m/s. However, the book says that the answer is 3.00m/s. This is for part A.

Homework Statement Let S and S' be two inertial frames of reference where S' is moving at a velocity of 0.6c relative to S. When x = x' = 0, t = t' = 0, where t and t' are time of the clocks on S and S' respectively and x and x' are the x-coordinates of the S and S' frames respectively. An...

Homework Statement A team of dogs drags a 114 kg sled 1.92 km over a horizontal surface at a constant speed. The coefficient of friction between the sled and the snow is 0.124. The acceleration of gravity is 9.8 m/s 2 . Find the work done by the dogs. Answer in units of kJ. Find the energy...

Hey guys, there's these questions in my hm that's really tough for me and i basically have no clue on how to do it. Any help is greatly appreciated 1.a) Give the numbers 1,1,2,3,4,5,5,6,7, If five numbers are randomly selected without replacement, how many different numbers can be formed if...

hi! i don't quite know how to start solving for this. i understand the problem and what it's asking for but i have no idea how to start solving for it. In a volleyball game, a player from one team spikes the ball over the net when the ball is 10 feet above the court. The spike drives the ball...

Homework Statement Uploaded the question below , Part B Homework Equations Φ=NBA EMF= (delta)Φ/(delta)t V=IR The Attempt at a Solution so i found the area (0.25x0.3) and then divided by two (=0.0375m^2) , then found Φ=80x1.4x0.0375=4.2wb However , in the marking scheme they multiplayed by...