Homework Definition and 998 Threads

I use this when making exams for all my courses. It goes in the preable or the very beginning of the .tex file. Note the use of the commands, I also include commands imported by the file macros! Macros is simiply a .tex file defining your own commands. I have included in another post a list...

Homework Statement Homework EquationsThe Attempt at a Solution ##C_p - C_v = p \frac{\partial V}{\partial T} ## Doing the above, I got ## R\{ 1+ \frac{bp} {RT^2}\}##, there is no square in the right factor. I want to know whether my answer is correct.

Homework Statement A beam of molecular oxygen containing 1010 molecules/cm3 and average speed of 500 m/s strikes (elastic collision) a plate at an angle of 30º with the normal direction. Calculate the exerted pressure on the plate. Homework Equations P = Impluse x Flux The Attempt at a...

A 50 kg box rests on the floor. The coefficients of static and kinetic friction are 0.70 and 0.50, respectively. a.) What is the minimum force required to start the box sliding from rest? b.) After the box starts sliding, the person continues to maintain that force. What is the...

Homework Statement Fill-in with the correct tank letter or the condition (eg. PPM of O2) Refer to above Chart A: __1. Which tank contained the lowest PPM of Oxygen? __2. Which of the 4 abiotic conditions(02, C02, PH, or Temperature) is most out of line in tank...A-G? __3. Which tank has a...

Homework Statement This is a problem from the Cambridge Natural Science Admissions Assesment. A student carries out an experiment to measure the speed of sound. A loudspeaker that emits sound in all directions is placed between two buildings that are 128 m apart as shown. The student and...

Hi all. I'm reviewing my daughter's science homework and I disagree with how things are being presented. I wanted some feedback from everyone here to get a sanity check on my own thinking. The exercise is this: answer whether these properties of matter are either an observable property or a...

Alright, first I should probably let you all know that this is very simple physics, so I'm just looking for a quick answer. 1. Homework Statement I'm trying to find a simple way to calculate the average velocity of an object where we know the average velocity during a number of segments of...

Homework Statement [/B] Phospine exist in three forms. known as the \alpha, \beta and \gamma forms. The \alpha and \beta forms are in equilibrium with each other at 49.43 \, K, and the \alpha and \gamma forms are in equilibrium at 30.29 \, K. Obtain the molar heat of transformation for the...

Homework Statement A small mass m is suspended from a string of length L. The body revolves in a horizontal circle of radius R with a constant speed v. Find the speed of the body and the period of the revolution. Homework Equations ΣFx = Tx = mV^2/r Period = (2πr)/V The Attempt at a...

Homework Statement Estimate the time between each photoflash of the apple in Fig. 2-18 (or number of photoflashes per second). Assume the apple is about 10 cm in diameter. [Hint: Use two apple positions, but not the unclear ones at the top.] Homework Equations All we have learned in class is...

Homework Statement A daring 510N swimmer dives off a cliff with a horizontal leap. What must his minimum speed be just as he leaves the top of the cliff so that he will miss the ledge at the bottom, which is 1.75m wide and 9.00m below the top of the cliff? Homework Equations s=1/2gt^2 ; v=s/t...

Homework Statement Maxine (mass m) slides down an icy slope then along a flat surface before coming to a stop. The slope has angle θ and height h. a. Derive a formula for speed at the bottom of the hill in terms of the angle of the hill θ, the height from which she starts h, and the...

Greg Bernhardt submitted a new PF Insights post 10 Math Tips to Save Time and Avoid Mistakes Continue reading the Original PF Insights Post.

Okay so I have a friend who has a 3rd grader and is 7 years old and he is having trouble completing this homework... we can't figure out how to do the problem on the 2nd page, we understand the example in the first page Page 1 Is the example page. I am going to attempt to translate to English...

<Moderator's note: Moved from a technical forum and thus no template.> Question: A certain amount of oil on the sea surface can be considered as circular form and the same thickness throughout its surface. At a certain time, the following are noted Data: Oil is supplied to the spot at 5m^3/min...

1. The problem is: In point form, outline the process through which electricity is generated, highlighting the energy transformations that occur. Then state an advantage and disadvantage for this type of electricity production. The attempt at a solution I will be describing the energy...

I am joining this forum to expand my knowledge on my favorite subject being physics. I may not be veyr active but if I have questions about homework or curiosity in general, I'll post here and hope for a response. Thanks

1. Homework Statement It's an auto closing gate. Two parts of the gate are identical. I had given to find the time taken to close the gate. The distance to close point (P) of the gate from closed event of the gate is given as "a". Sorry for my bad English. What i need to know is how the two...

Homework Statement Homework Equations $$\frac{\partial S}{\partial u}\Bigr|_{v} = \frac{1}{T}$$ $$\frac{\partial S}{\partial v}\Bigr|_{u} = \frac{-P}{T}$$[/B] The Attempt at a Solution a.) $$\frac{S}{R} = \frac{UV}{N} - \frac{N^3}{UV}$$ $$\frac{S}{R} = \frac{UV}{N} - \frac{N}{uv}$$ $$...

Homework Statement A mixture of hydrogen, carbon monoxide and carbon dioxide is being fed to a compressor at 2.0 bar and 25 C. The overall flow rate is 17.47 SCMS and its composition is 73.5 mol% H2, 13.7 mol% CO and the balance CO2 The compressor operates adiabatically and reversibly with a...

Homework Statement Question on worksheet: What is the random uncertainty in this set of measurements? Use the instrumental uncertainty to limit the number of digits in your random uncertainty result. Data for dropping a pencil from a height of one meter using a stopwatch that measures to the...

Most people don't get to cal 1 in high-school by the time they are seniors. People are excepted to get ready for cal 2 by the time they get to college. People don't get to cal 1 because they don't study at their home. However, in my personal opinion, is homework a mistake to give to students...

Hello all; this my first time ever taking physics, and I am in dire need of some help with homework. I've had an attempt at part A (please take a look and provide feedback), but have no clue where to even begin on part B (how would I go about calculating questions 5, 6, and 7, to be precise?)...

Hi, I'm supposed to linearize this set of data: "Below is a data set which includes information about the motion of the objects in the solar system. Note: the periods are listed in Earth years (time it takes the Earth to complete one orbit around the Sun) and the average distances are reported...

Homework Statement Homework EquationsThe Attempt at a Solution I'm not sure how to even begin this problem. My notes mentioned something about a Mobius Transformation but that's not something that I've been taught, and certainly not something I'm familiar with. Any advice would be greatly...

Hi guys, could someone please have a look at my solution and let me know if it makes any sense. Homework Statement Homework Equations N/A The Attempt at a Solution [/B]

Homework Statement A research worker is irradiating some drug samples in an x–ray beam. The tube is running at 60kVp with a tube current of 4mA. Although the ‘shutter open’ lamp is extinguished, indicating the shutter is closed , it is faulty and the researcher loads his samples with the...

< Mentor Note -- thread moved to HH from the technical forums, so no HH Template is shown > Here's a question from a national-level engineering exam in India called GATE (2017). It is for 2 marks, numerical answer type. Two synchronous motors A and B in parallel with identical O.C...

Really struggling with this! Here is the data: Concentration of NaOH: .104M Mass of Aspirin #1: .367g Mass of Aspirin #2: .365g Volume of NaOH mixed with Tablet 1: 50ml Volume of NaOH mixed with Tablet 2: 50 ml Trial 1 Mass of Na2CO3: .065g Initial volume of HCl: 18.80mL Final Volume...

I= Current flowing V1= Voltmeter 1 V2= Voltmeter 2 My question is that if there would be any difference between the readings of V1 and V2? We know that: By Ohm's law: V= I.R also: Combined resistance of R1 and R2 will be: 1/RCombined Resistance of R1 and R2= 1/R1+1/R2 The reading in V2...

Homework Statement A ship traveling 55 degrees [W of N] is 65km farther north after 3.0h. What is the ship's velocity. Homework Equations sin, cos, tan? The Attempt at a Solution I know that Vground= Vair + Vwind, and that Vground = Vboat + Vcurrent, but I'm not sure if that is even relevant...

Homework Statement for number 3,4,5 I'm still tryingHomework Equations PV/T = PV/T q = ΔU + W W = P ΔV The Attempt at a Solution (3) I used PV/T = PV/T to find the ΔT for each process for A→B I find PV/TA = P3V/TB ----- TB = 3TA (T increase) for B→C I find P3V/TB = 4P3V/TC ----- TC =...

Is there any chance someone can help me solve this? Music teacher with absolutely no idea how to solve this. Thanl you so much. ? w!81 = 26r3 (the goal is to find the first number, and explain how you figured it out)

Homework Statement An ideal gas with Cv = 5 2R, and γ = 1.4 starts at a volume of 1.5m3 , a pressure of 2.0×105Pa ,and a temperature of 300K. It undergoes an isobaric expansion until the volume is V , then undergoes an adiabatic expansion until the volume is 6.0m3 , and finally undergoes an...

Homework Statement An ideal gas with Cv = 5/2R, and γ = 1.4 starts at a volume of 1.5m3 , a pressure of 2.0×105Pa, and a temperature of 300K. It undergoes an isobaric expansion until the volume is V , then undergoes an adiabatic expansion until the volume is 6.0m3 , and finally undergoes an...

A refrigerator operates on a Carnot cycle. In this cycles, it absorbs 120 J of energy at a temperature Tc while 300 J of work is done on the gas undergoing the cycle. How much energy is exhausted as heat during this process? The answer is 420 J. I am unsure of where to start for this...

A bar of iron is 0.5m long, 0.2m wide and 0.1m high (which means its volume is 1.0 × 10−2m3 and its surface area is 3.4 × 10−1m2 ). Iron has a density of 7900 kg m3 , a heat capacity of 400 J kg◦C , and a coefficient of linear expansion of 1.2 × 10−5 . The bar of iron is initially at 600K...

Homework Statement q1= 5 x 10^-6C position (1;2,-1) q2= -3 x 10^-6 C position (-2,1,3) a) what is the electric force caused by q2 on q1? (vector notation) b) what is the electric field at (0,0,0) Homework Equations F = kq1q2/r^2 E= F/q The Attempt at a Solution I really don't...

Homework Statement ##(2x + 3y + 1)dx + (4x + 6y + 1) dy = 0## ##y(-2) = 2## Homework EquationsThe Attempt at a Solution Let ##z = 2x + 3y## then ##z^\prime = 2 + 3y^prime## ##\displaystyle \dfrac{(z + 1)}{2z + 1} + \dfrac13\left({dz \over dx} - 2\right) = 0## ##\dfrac{dz}{dx} = \dfrac{z-...

Homework Statement This is a question from the test i had today in which we had to look at certain C code segments and deduce which code part is missing in order for the program to do what we desire. Part b) was a short questionnaire to test our knowledge about c types and declarations. Part a)...

Homework Statement A picture of the problem is provided in the attachment Homework Equations there is no special relations except I= Is x e^(vd/Vt) The Attempt at a Solution i have a solution for from the solution manual but i do not understand it like the I2 equation i don't get reasonable...

Homework Statement see pic in the attachment beta = 100 Homework Equations Rinput=Rth Vinput=VTH iB= ic/beta IE=ic /alpha iB=iE/(beta+1) gm=IC/VT Avo=-gmRC Av=-gm(RC||RL) Gv=-Beta[(RC||RL)/Rsig+(beta+1)re re=alpha/gm The Attempt at a Solution solving each stage separately. First DC analysis...

I can never get started on, or never get motivated with my math homework. I know this seems like a stupid question, but if anyone has any tips, they would be helpful. Thanks!

Homework Statement My task is to write a program that reads from the .txt file into a list which contains two parts, the part of the text from the file and a pointer to the next element. Here are the specifications of the problem: When reading from the file you should separate the letters from...

Homework Statement There's two blocks of mass m_{A} and m_{B} which are linked by an ideal string. The block of mass A descends at constant speed. There's no friction. If the pulley is ideal, which one of the following is true[/B] Homework Equations Newton laws and trigonometry I...

Homework Statement In-phase light from a laser with an effective power of 2x105J and a wavelength of 1064nm is sent down perpendicular 4km arms of the LIGO detector. (i) Determine the number of photons traveling in the interferometer arms. (ii) Assuming the detector is sensitive enough to...

Homework Statement Problem: http://imgur.com/a/Sw2zA Hi all, I was given this problem as homework and I have almost no clue on how to solve it. I have tried for some time with no luck. Homework Equations We learned about kinetic and potential energy as well as work. W = F*d W = delta KE PE =...

Homework Statement A projectile is fired vertically from the Earth's surface with an initial speed of 11.4 km/s. Neglecting air drag, how far (in meters) above the surface of the Earth will it go? Homework Equations (1/2)mv^2 -GmM/R The Attempt at a Solution KEi+PEi = KEf+PEf (1/2)mv^2 -...

Homework Statement The decomposition of phosphine 4PH3(g) + P4(g) + 6H2(g) is first-order with respect to phosphine with a rate constant k = 0.0155 s-l at 953 K. If the decomposition occurs in a constant-volume batch reactor at 953 K, calculate, for 40% conversion of PH3, (a) the time...