Homework Definition and 998 Threads

Chemistry Homework -- the empirical formula of crocetin Homework Statement Crocetin consists of elements carbon, hydrogen and oxygen. Determine the empirical formula of crocetin, if 1.00g of crocetin forms 2.68g of carbon dioxide and 0.657g of water when it undergoes complete combustion...

I tried looking at the other threads on this but they seem incomplete. I would like someone to check my work. Homework Statement Two boats are heading away from shore. Boat 1 heads due north at a speed of 3 m/s relative to the shore. Relative to Boat 1, Boat 2 is moving 40° north of east...

Homework Statement We have a transformer, the primary coil has 120V and secondary coil has 6V, if you put 8V in secondary coil, what will be the voltage in the primary coil. Homework Equations v1/v2 = n1/n2 where v is voltage and n is turns The Attempt at a Solution So i was...

Can you check my physics homework please?? Homework Statement My physics project includes predicting (1) the time it takes a ball to go down a slide http://i.imgur.com/TfQI87H.png I'm not sure if it's right though. (2) finding the coefficient of friction between me and the slide...

Homework Statement A 165g plastic block is set up against a spring. The block rests on a smooth (I'm assuming this implies that there is no friction involved) horizontal surface. The block is pushed into the spring, compressing it a distance of 15.0 cm and released. The spring constant is k=...

A spacecraft is coasting toward Mars. The mass of Mars is 6.4 × 1023 kg and its radius is 3400 km (3.4 × 106 m). When the spacecraft is 8500 km (8.5 × 106 m) from the center of Mars, the spacecraft 's speed is 2250 m/s. Later, when the spacecraft is 5300 km (5.3 × 106 m) from the center...

Homework Statement Hey everyone, I'm new to this forum so Let me first introduce myself to the community. I am a grade 11 High school student from Toronto, Canada. I have joined this forum in hopes of gaining access to support whenever i need help on my Physics homework. I have a question.. So...

Astronomy homework question -- stars emitting in infrared Dear All, Hello! This is my first post. I am taking a distribution introductory astronomy course (low on math) and am having trouble with this question: Which object emits more intense infrared radiation: _ the Earth _ the Sun...

So being as much of a simpleton as me I don't understand slope intercept form. I can graph simple linear equations like x=y+3 and things like that but I want to learn about slope intercept form and what it is(I have been entreating people like my friends, math teacher and parents to help me so...

Homework Statement Wondering if I did this right. Find the centroid of the region shown , not by integration, but by locating the centroids of the rectangles and triangles and using additivity of moments. Homework Equations I will give you the coordinates since I can't draw it. For...

I'm starting to get to a point where the numbers are getting sometimes well beyond 3 digits in length and, I'm constantly amazed at the fact that there are usually no decimals anyplace in the actual problem, and I was wondering how long does it take to find questions that don't have decimals in...

Hello. I am studying differential calculus and I need help on what these questions are asking and how to solve them. I have attempted some of the question but I need clarification. This week is mainly focused on learning the Quotient Rule. Please help me 1. (a) Differentiate y = (x - A)/(x -...

Homework Statement You're driving down the highway late one night at 18m/s when a deer steps onto the road 41m in front of you. Your reaction time before stepping on the brakes is 0.5s and the maximum deceleration of your car is 12 m/s/s Homework Equations 1) How much distance is...

Homework Statement A 15.0 g bullet with a speed of v = 235 m/s is fired into a block of wood that is initially at rest on a frictionless surface. The block of wood is attached to a horizontal massless spring with a spring constant k = 195 N/m that is initially uncompressed. The other end...

Homework Statement Hi, I have a really short (and dumb) question. In one of my homework problems they talk about a vector w, such that w=e1+e2+e3. (In R3.) The Attempt at a Solution I guess they mean that: e1=(1,0,0), e2=(0,1,0) and e3=(0,0,1). So w=(1,1,1). Right?

Homework Statement An unmarked police car traveling a constant 80km/h is passed by a speeder traveling 135km/h. Precisely 3.00s after the speeder passes, the police officer steps on the accelerator; if the police car's acceleration is 1.50m/s2 , how much time passes before the police car...

Homework Statement Homework Equations The Attempt at a Solution $$Δ{ V }_{ H }=\frac { IB }{ nqt } \\ 9.6*{ 10 }^{ -6 }=\frac { 50*1.3 }{ n*e*3.3*{ 10 }^{ -4 } } \\ n=1.28*{ 10 }^{ 29 }\quad electrons/{ m }^{ 3 }$$

[b]1. I have to calculate the weight of an astronaut, whose mass is 72 Kg on the surface of different planets, but in the table telling me the Acceleration due to gravity (or Gravitational Field Strength) it there is also a column about whether the planet has an atmosphere. Is that relevant...

Homework Statement This is not really a problem but I was going over my lecture notes and I see \mathscr{H}=\frac{1}{2}\left(\pi^{2} + \vec{\nabla}\phi \cdot \vec{\nabla}\phi + m^{2}\phi^{2}\right) and \frac{\partial\mathscr{H}}{\partial\phi} = -\nabla^{2}\phi + m^{2}\phi Homework...

Homework Statement Hi! I have a problem with an assignment and need som help. The question is: You’ve just completed an analysis of where the Space Shuttle must be when it performs a critical maneuver. You know the shuttle is in a circular prograde orbit and has a position vector of: ro=...

Homework Statement 1)The pressure on an ideal gas is cut in half, resulting in a decrease in temperature to 0.604038 of the original value and a change in the volume. Calculate the ratio of the final volume to the original volume of the gas. 2) Steam moves into the cylinder of a steam engine...

Homework Statement In deriving the formula div v = \frac{∂v_{x}}{∂x} + \frac{∂v_{y}}{∂y} + \frac{∂v_{z}}{∂z} we used a rectangular solid infinitesimal volume; however, any shape will do (although the calculation gets harder). To see an example, derive the same formula using the prism-shaped...

Homework Statement A particle is projected vertically upwards at 30 m/s. Calculate (a) how long it takes to reach its maximum height, (b) the two times at which it is 40 m above the point of projection, (c) the two times at which it is moving at 15 m/s.[b]2. Homework Equations [/b final...

Homework help needed! the problem is stated as follows: A playground is on the flat roof of a city school, 5.1 m above the street below (see figure). The vertical wall of the building is h = 6.20 m high, to form a 1.1-m-high railing around the playground. A ball has fallen to the street below...

Hi everyone. In my class we are now learning about Quantum theory & the whole "shananigans". Yesterday we talked about orbitals (s, p, d, f, g). In one of the classes my Physics teacher said that the letter "l" (lowercase L) indicates the sub-shell and "m (sub) l" the location of the orbits...

Homework Statement The homework my professor gave me is... We have a tank filled with a liquid, it has a hole at the bottom of the tank. The tank does not taper. the hole is at the bottom and not on the side. No extra pressure is applied to the liquid to help it drain and the top of the...

1. A student is performing an experiment with two identical small metal balls, A and B. Initially, Ball A contains 6.0-uC net charge with unknown sign and Ball B is neutral. The student brings them in contact and then separated them by 20cm. Both of the balls are remained isolated. Is the...

My daughter came home with this assignment (see PDF link below) tonight. Am I right to be concerned when they equate power with force, and size with mass? Or am I just over-blowing this for 2nd grade? https://dl.dropboxusercontent.com/u/49570443/homework.pdf I explained to her that push...

Homework Statement I'm a chemist, so forgive me. I'm looking at Leonard Susskind's course on 'Quantum Entanglement', and we've just started on Qbits. Electron spin: we have two column vectors (1,0) and (0,1) to represent the two states, call them 'up' and 'down'. The vector for the...

Hi there, I just would like if someone could check over my work on my current homework assignment involving fluid dynamics. Homework Statement 1) Calculate the absolute pressure at an ocean depth of two kilometers. Assume the density of seawater is 1000 kg/m3, the density of air is 1.3...

Homework Statement A mass of 1000 kg drops from a height of 10 m on a platform of negligible mass. It is desired to design a spring and dashpot on which to mount the platform so that the platform will settle to a new equilibrium position 0.2 m below its original position as quickly as possible...

Uncertainty partial derivatives Homework Statement 1 a) Give expressions for the uncertainty in both the area and volume of a right circular cone with radius R and height H and side length S. Assume that the radius has uncertainty σR and the height has an uncertainty σH. <----First part...

Homework Statement Infrared telescopes, which use special infrared detectors, are able to peer farther into star-forming regions of the galaxy because infrared light is not scattered as strongly as is visible light by the tenuous clouds of hydrogen gas from which new stars are created...

1. So for today's exam, I was given this equation, and I was required to get the value and units of K: T4 = (4K∏4)/g2 - (8d∏4)/g2 I had to follow an experiment, plot the results, get the gradient. After getting the value of g, I was required to find the value of K, and its units. T4 has...

Homework Statement f(x) = [1 - tan(x)]/[1 - √2 sin(x)] for x ≠ π/4 = k/2 for x = π/4 Find the value of k if the function is continuous at x = π/4 The Attempt at a Solution This means that lim x → π/4 f(x) = k/2 I put x = (π/4 + h) and then...

Homework Statement I am having problems with the following problem: "For a noninteracting gas of N particles in a cubic box of volume V = L^3 where L is the length of the side of the box, find the solution, \rho (\mathbf{p}^{3N},\mathbf{q}^{3N},t) , of the Liouville equation at time t, where...

If I throw a ball vertically in the air and catch it again at the exact same height after 3.6 seconds. (looking away from air resistance) So the question is: 1. How big is the starting speed? (v0) And how far in the air would the ball go? 2. If we were not to catch the ball it would've hit the...

Moved to homework area sorry. -kiyoshi7

Homework Statement A block of mass m is at rest at the origin at t=0. It is pushed with constant force F0 from x=0 to x=L across a horizontal surface whose coefficient of kinetic friction is μk=μ0(1−x/L). That is, the coefficient of friction decreases from μ0 at x=0 to zero at x=L...

Homework Statement Doug pushes a 5.30 kg crate up a 2.20-m-high 20 degrees frictionless slope by pushing it with a constant horizontal force of 27.0 N. What is the speed of the crate as it reaches the top of the slope? a) Solve this problem using work and energy. Homework Equations...

Homework Statement Which of the following aqueous solutions has a Cl– concentration of 2 m at 25°C? A. 271 g of HgCl2 in 55 mol of H2O B. 271 g of HgCl2 in 22.5 mol of H2O C. 53 g of NH4Cl in 55 mol of H2O D. 53 g of NH4Cl in 22.5 mol of H2O. Correct Answer...

Thank you for helping! I got it :)

Homework Statement I am having a hard time understanding the length measurement in the problem. We went over this example in class and the length, L, was something I didn't realize until now. Question: A 6-ft-long steam pipe is made of A-36 steel with σ=40 ksi (yield stress). It is...

Homework Statement Alpha Centauri is ##4.4## light years away from Earth. What speed ##u## would a spaceship headed towards Alpha centauri had to have in order to last ##t' = 10## years for a passanger onboard? Homework Equations I know equations for time dilation, length contraction...

Homework Statement Let a be a real number such that 1 < a < 2 ,{an} is a sequence defined by a1=a, an+1=|an|-1 (n=1,2,3...) And put sn=a1+a2+a3+...an i)Find the a4,a5,a6,a7 i)Find a4,a5,a6,a7 The Attempt at a Solution I don't even know how to start.Maybe someone could give me an idea.

Homework Statement Find the direction of E at rho where is the electric field http://i.imgur.com/37ohyME.jpg Homework Equations F=KQq/r^2 The Attempt at a Solution I thought I might just have a vector pointing right from the +2Q and another pointing up from the +3Q and just...

Physics Homework Help -- Force when kicking a ball Homework Statement I have a few physics problems on my homework, I need help. A player kicks a 0.5kg ball with a force of 50N, what is the force on his foot? Homework Equations F = Mass * Acceleration The Attempt at a Solution...

Homework Statement Sketch the region R bounded by the curves y = x, x = 2 - y^2 and y = 0. This is the initial part of an integral problem and I'm just curious about the method here. Homework Equations The Attempt at a Solution So, would it be proper to take the x = 2 - y^2...

Homework Statement Answers were told to us to be F = 2.91 N Ft1 = 13.32 N Ft2 = 3.36 N Homework Equations Fx = Ft2 cos(θ) - F = 0 Fy = Ft2 sin(θ) + Ft1 - Fg = 0 Torque equation -FgDg - Ft2D1x cos(θ) + Ft2D1y sin(θ) = 0 The Attempt at a Solution I plugged in all of the information i had...

Homework Statement I have just planted a new tree. To support the tree in bad weather, I attach guy wires from the trunk of the tree to stakes in the ground. I cut 32 feet of wire into four equal lengths to make the guy wires. I attach four guy wires, evenly spaced around the tree. I put...