Work done Definition and 1000 Threads

Suppose I have a ball colliding with a surface at an oblique angle. I want to know what work will be done on the surface. Now, there is kinetic energy associated with the tangential and normal velocity of the ball. Can I say that the kinetic energy of the ball associated with the normal...

Homework Statement calculate the work done by a force F=(4.00yj)N(a varying force) that acts on an object that moves along the Y-axis, from Y=-2.0m to Y=3.0m Homework Equations non given but i assume it is W=fscos(θ) The Attempt at a Solution attempted to use W=fscos(θ) but only...

I am having trouble with this question:( Any advice. One mole of an ideal gas at a pressure p0 and a volume V0 undergoes the following changes in order: (i) expands to twice its volume at a constant pressure (ii) heats to twice its initial pressure at constant volume (iii) is compressed to...

Determining the work done on the puck using conservation of angular momentum?? Help! This is what I did... 1) Given mpuck = 0.300 kg rinitial = 0.4 m vinitial = 0.6 m/s mpuck = 0.300 kg rfinal = 0.15 m vfinal = ____ m/s ƩW = KEfinal - KEinitial 2) KEinitial = (1/2)mv2...

What is given: Torque: τ = 34.5 N * m Inertia: I = 0.130 kg * m2 Angular speed: ω = ? Work done by a constant Torque: τΔθ = (1/2)Iωf2 - (1/2)Iωi2 Angular displacement: Δθ = 17.1 rev/s = 107.442 rad/sτΔθ = (1/2)Iωf2 (34.5)(107.442) = (0.5)(0.130)ωf2 3706.765 = 0.065ωf2 57027.156 = ωf2 238.8 = ω...

Homework Statement A father pushes horizontally on his daughter's sled to move it up a snowy incline, as illustrated in the figure, with h = 4.4 m and θ = 10°. The total mass of the sled and the girl is 35 kg and the coefficient of kinetic friction between the sled runners and the snow is...

Homework Statement A 2.75-kg potted plant rests on the floor. Determine the work required to move the plant at a constant speed along the shelf for 1.07 m where the coefficient of kinetic friction is 0.549 The Attempt at a Solution I found the Fn: Fn = mg Fn = 26.95 N Ff = Fnμ Ff...

Homework Statement The density of solid gold at 20°C is ρ = 19.3 g/cm3. When it is liquid at 1064°C the density of the liquid state is decreased: 17.3 g/cm3. How much work does a block of gold of mass 407 kg do if it is heated at p = 1.0 atm from 20°C to 1064°C? Homework Equations...

For reversible, work done =∫P dV Then for irreversible ,we can't use the above equation, because we have to consider the dissipative work. Correct? Thank you

According to work - mechanical energy theorem , W = K(final) - K(initial) + U(final) - U(initial) . . . . (1) as we define Potential energy as negative of work done by conservative force and assuming that the only force in this situation is Spring force then , W(spring) = K(final) -...

Homework Statement Homework Equations F=ma W= Fdcosθ The Attempt at a Solution I first found the acceleration: t= d/v t= 37m/28m/s = 1.32s a = v/t a = 28m/s / 1.32s a= 21.21 m/ss Second, the force: Fclub - Fgsinθ = ma Fclub = a +gsinθ Fclub = 21.21m/ss + 9.8m/ss...

Homework Statement A car weighing 1500kg traveling at 20m/s brakes, and takes 50m to stop. Part A) Calculate the work done Part B) Calculate the power needed to stop the car Known starting variables are.. u=20 v=0 s=50 m=1500 Homework Equations P=Fv W=Fs F=ma s=1/2(u+v)t...

I need some help in thermodynamics (chemistry). I'm currently studying in class 11th, preparing for IIT-JEE. I am looking for a precise comparison between the work done in different types of thermodynamic processes on gases. I searched the net a lot for this stuff, but all i got was...

The formula is m*g*h which translates to m*g*d*sinθ right? I have it written down as m*g*d*cosθ on my formula chart for some reason which doesn't make sense, and I want to reassure myself.

Homework Statement Is it possible to have a scenario like this. An object is pushed up a slope and it has no initial speed. When it reaches the top the object's speed is also zero. So it's like work done by push+work done against friction=mgh. It doesn't seem plausible to me. Homework...

Alright so I have a question on the work done with constant acceleration up a hill. I was working an example problem that asked for the work a hiker must do on a 15.0 kg backback to carry it up a hill of height h = 10.0m with the hiker keeping a constant velocity...

Homework Statement i've been stuck on this problem for about 45mins. A constant external force P = 160 N is applied to a 20 kg box,which is on a rough horizontal surface. The force pushes the box a distance of 8.0 m, in a time interval of 4.0 s, and the speed changes from v1 = 0.5 m/s to v2 =...

Homework Statement A string pulls a 50kg block 10m up and the acceleration of the block is g/10. What is the kinetic energy of the block? Homework Equations W = Fd W = 1/2*mv^2 The Attempt at a Solution 1st attempt (each force work separately) The work done on the block from the...

Homework Statement In the system shown in the figure, suppose the block has a mass of 2.7kg , the spring has a force constant of 540 n/m , and the coefficient of kinetic friction between the block and the floor is 0.16. Find the work done on the block by the spring and by friction as the...

Work done against gravity by Wonder Woman Homework Statement Wonder Woman, whose mass is 52 kg, is holding onto the free end of a 13.0 m rope, the other end of which is fixed to a tree limb above. She is able to get the rope in motion so that she can reach a ledge when the rope makes a 60...

Two charges q1 = 3.0µC and q2 = −4.0µC initially are separated by a distance ro = 2cm. An external agent moves the charges until they are rf = 5cm apart. a) How much work is done by the electric field moving the charged from ro to rf? Is it negative or positive? What is the work done by a...

Homework Statement There's a mass (16.6 kg) on a surface with kinetic coeficient of friction 0.181. it's being pulled by a constant force of 161 N at 26 degrees above the horizontal. The block is displaced 39.1 meters. Calculate the work done by friction.Homework Equations Friction = (mu)Fn...

Suppose there are two parallel plates with charges of opposite polarity on the faces towards each other (a charged capacitor, disconnected) and we send a charged particle through the field between them from one end. When the particle comes out the other end, it has more kinetic energy, because...

Calculating Work Done by Friction in a Circular Track (Answered) Homework Statement A small block with mass 0.0425kg slides in a vertical circle of radius 0.400m on the inside of a circular track. During one of the revolutions of the block, when the block is at the bottom of its path, the...

Homework Statement How much work is done by the electric field in moving a particle from (a,a,0) to (a,a,a) in a region where the electric field is: E = zye_x + yxey + xyezHomework Equations F=qE W = integral F dot dl V(2)-V(1)= - integral E dot dl The Attempt at a Solution I know how to do...

Please help me to solve the following question... I am really stuck. 1. Two children of mass 40 kg and 50 kg are holding on to the ends of a rope which passes over a thick horizontal branch of a tree. The parts of the rope on either side of the branch are vertical and the heavier child is...

Homework Statement A raindrop of mass 3.35x10-5 falls vertically at constant speed under the influence of gravity and air resistance. Model the drop as a particle. As it falls 100m, what is the work done on the raindrop. (a) by the gravitational force and (b) the air resistance...

Homework Statement How to find the work done by a variable force in (two dimension) When F = ax^2 i + b y^3 j If a subject move from (x1,y1) to (x2, y2) Homework Equations F = dW/dr The Attempt at a Solution I tried to solve them separately by x-direction and y-direction, and then I added...

A crate is dragged 15m along a horizontal surface by a rope which makes an angle of 37° with the horizontal. How much work is done?

Hello, everyone I would very much appreciate some help on this Intro to Thermo 2 problem if someone could give advice even a little would be helpful.1. Air (for this example, an ideal gas) is being used to produce work in a turbine and then is expanded to atmospheric pressure (101.2 kPa)...

Homework Statement A student performs a combustion experiment by burning a mixture of fuel and oxygen in a constant-volume metal can surrounded by a water bath. During the experiment, the temperature of the water is observed to rise. Regard the mixture of fuel and oxygen as the system. a) Has...

Homework Statement A 95-g bullet is fired from a rifle having a barrel 0.540 m long. Choose the origin to be at the location where the bullet begins to move. Then the force (in Newtons) exerted by the expanding gas on the bullet is 16200 + 9400x - 23750x2, where x is in meters. (a) Determine...

Homework Statement The problem, basically, is very simple but, it is confusing me. It says: "There is block on a moving train, which is being pushed by a man. The man applies force F to displace the block by s wrt Train. The moves S in that period. Find work done on the block by the force wrt...

Homework Statement Homework Equations What is the work done by a satellite moving around the Earth at constant altitude. Work done = Force x displacement. The satellite has a mass and displacement. Should it have work? The Attempt at a Solution

Homework Statement I have a current problem set question about the work per unit area required to separate infinite sheets of charge with equal and opposite charge densities from a separation of d to a separation of 2d. Homework Equations U=(1/8∏)∫E2dV W=∫F*dr E=4∏σThe Attempt at a Solution I...

Homework Statement In the figure shown a square plate of mass M and side of length L is fixed at the center . The force F makes the square plate rotate. The force is always perpendicular to the side. Find the work done by the force. Homework Equations Work = torque x θ The Attempt...

Homework Statement Pt. A) A gas is compressed at a constant pressure of 0.632 atm from 7.11 L to 5 L. In the process, 440 J of energy leaves the gas by heat. What is the work done on the gas? Answer in units of J Pt. B) What is the change in its internal energy? Answer in units of J...

Homework Statement Find the amount of work (ω) done by moving a point from (2;0) to (1;3) along the curve y=4-(x^2), in the effect of force F=(x-y;x). Homework Equations The Attempt at a Solution ω = ∫((x-y)dx + xdy) ω = ∫(x-4+x^2)dx + ∫√(4-y) dy In the end, I get this...

"Work done by an electric FIELD" = "Work done by electric FORCE"?? Homework Statement Problem 1 If the electric field does negative work on a negative charge as the charge undergoes a displacement from position A to position B within an electric field, then the electrical potential energy...

Homework Statement Determine the work done by the Force F = yi(hat) - xj(hat) on an object that travels from point A (a,0) to point B (-a,0) a) along an elliptical path described by x=acosθ, y=bsinθ b) along a straight line from A to B c) From these results, can we determine whether or...

Homework Statement The three ropes shown in the bird's-eye view of the figure (Figure 1) are used to drag a crate 3.2 across the floor.How much work is done by each of the three forces? Then the picture is Force one is 600N 20o above the x-axis force two is 410N 30o below the x-axis and force...

Hi Not a homework question, just a fool tinkering... I have been messing around with the concepts of a stirling engine, and have been looking at other engines which do not use an explosive mixture (petrol etc) as their heat source. I have to say I am having trouble getting my head...

I come from a civil engineering background and I'm about to start a masters in nuclear energy. I have no experience in thermodynamics and I've been doing a bit of revision before the course commences to get me up to speed but I'm really stuck on the following problem although it should be pretty...

Now that I am making progress, I am ready to ask more complex questions :approve: Please correct me where my reasoning is wrong. Consider a cylindrical piston in which an ideal gas is sealed. The gas is initially at temperature T. The piston is well insulated, so that all thermodynamic...

Homework Statement A box of weight 200N is pushed so that it moves at a steady speed alog a ramp, through a height of 1.5m. The ramp makes an angle of 30° with the ground. The frictional force on the box is 150N while the box is moving. What is the work doe by the person? Homework...

Homework Statement The fastball of a famous pitcher in the National League has been clocked in excess of 95 mph. Calculate the work done by the pitcher in accelerating the ball to that speed. The mass of a baseball is 0.145 kg. mass = 0.145 kg final velocity (in m/s) = 42.4688 m/s...

Let say we have a horizontal mass-spring system oscillates without friction on a smooth surface. One side of the spring is attached / fixed to a wall. The other is where the mass is attached to. Let say we choose our system to be the mass and the spring (negligible mass), so our free body...

capacitor -- Work done to charge it up If we imagine a capacitor as two conductors held a distance d apart from each other, we can find easily that the total charge and the potential are proportional: Q = CV To find the energy stored in a capacitor you can imagine taking a tiny chunk of...

In physics, work is said to be done by a force. In the field of electricity, work is done by an electrical field. In thermodynamics, work is done by a system. This is kind of confusing and makes me wonder, what is actually the thing that does work? Is it the object, the force field or the force...

Homework Statement http://s9.postimage.org/5iw5rixyl/image.jpg (sorry doesn't let me embed) Homework Equations P1V1=P2V2 and PV=nRT I know that Work done by gas from a --> b = (nRT)*Integral(V2/V1) My question is do i use PV=nRT to find N? and if T is constant (isothermal) what do I plug in...