Work done Definition and 1000 Threads

  1. B

    Work done and total heat transfer for piston-cylinder device

    Hi everybody, this question is on an old exam paper given to us for exam prep purposes. No answers have been supplied however. Am I on the right track? Question: A mass of 0.2kg of saturated refrigerant-134a is contained in a piston-cylinder device at 200kPa. Initially 75% of the mass is in...
  2. S

    Calculating Power and Work Done for a Punch

    can i say the work done on the punch of frighter??, i mean the force of the punch and the distance traveled by the punch. example, the force of punch is 100N and the distance for punch from the body to hit the target is 0.5m. work done = 100 X 0.5m = 50J and the power of the punch is...
  3. M

    T: What is the net work done by an Otto engine?

    Homework Statement Show that the net work done by the otto engine per cycle is Cv(Tc - Tb)(1 - Ta/Tb) PV diagram: [PLAIN]http://www.antonine-education.co.uk/physics_a2/options/module_7/topic_4/Otto_indic.gif Homework Equations Work done by a kmole of gas expanding irreversibly and...
  4. O

    Work done against gravity on a right circular cone

    Homework Statement A right circular cone has vertex down and is 10 feet tall with base radius 5 feet. The cone is filled with a fluid having varying density. The density varies linearly with distance to the top. Here "varies linearly" means the quantities are related by an equation of at most...
  5. O

    Find work done pulling sled with rope

    Homework Statement A loaded sled is pulled by means of rope that makes an angle of 45 with the horizontal. If the mass of the sled is 60 kg and the coefficient of friction is .0200, how much work is done in pulling the sled at constant velocity along a level road for a distance of 1.00 km...
  6. A

    How do you calculate the work done against gravity?

    Please help me ! If a 3.0j of work is done in raising 175 g apple , how far is it lifted?
  7. P

    Work Done by Gas in Carnot Cycle

    Hi, I was thinking about the isothermal and adiabatic expansions in the Carnot Cycle and I was wondering: In these processes, the gas is doing work. In the adiabatic change, the pressure (force), acts over a distance (expansion) transferring energy (Kinetic Energy) - but this is an adiabatic...
  8. P

    How Is Work Calculated in a Force Field Along a Parametrized Curve?

    Find the work done by the force field F= 3yi - x^2j in moving a particle along the curve y=x^(1/2) from (1,1) to (4,2) so i parameterize and get x=1+3t, y= 1+t so 3(1+t)-(1+t)^2 then take the derivative of x and y and multiple to ge 9(1+t)-(1+t)^2 and i integrate that from...
  9. R

    Speed as a ratio, but what about work done and moments?

    Hi all, Speed is a ratio of the distance traveled per unit time. But what then is work done and moments? For example, work done is force multiplied by the distance traveled in the direction of the force. But how would you explain the rationale of multiplying these two quantities? As...
  10. A

    What is the work done by gas, given V, T and P

    Homework Statement 0.5 m3 of air is located in a vessel. Their temperature is T1=0oC and the pressure is p=3·105. What work will be done when heating the gas with constant pressure (isobaric process) to T2=100oC? Homework Equations I was unable to find any equation regarding to the...
  11. H

    How to find work done in exact values?

    10N force acting in the direction of the vector (1, 1) moves an object from P (-2, 1) to Q (5, 6), calculate the work done. The Attempt at a Solution I can do this question correctly except I only know how to do it using decimals but the answer is in exact values of 60√2J. I can't figure out...
  12. E

    Work done by a distributed force on a string

    Hi All I'd like to know how I could calculate the work done by a distributed force on a string. Let's say the force at a point x at a time t is given by F(x,t). Now the instantaneous amplitude of the string is given by y(x,t), say I think that the work done by the force in...
  13. I

    Work done by liquid's frictional viscosity

    Homework Statement A 0.75 sphere is dropped through a tall column of liquid. When the sphere has fallen a distance of 2.0 m, it is observed t have a velocity of 2.5 m/s. How much work was done by the frictional viscosity of the liquid? PLEASE EXPLAIN-- I really would like to understand this...
  14. D

    How Is Work Calculated in a Vector Field?

    Homework Statement Find the work done by the force field F in moving an object from P to Q. F(x,y,z)=10y^(3/2)i+15x\sqrt{y}j P(1,1), Q(2,9)Homework Equations W = \intF dot drThe Attempt at a Solution I have no clue how to do it
  15. T

    How Does Entropy Change and Work Done Relate in a Reversible Ideal Gas Cycle?

    Figure 20-29 shows a reversible cycle through which 1.00 mol of a monatomic ideal gas is taken. Assume that p = 2p0, V = 2V0, p0 = 1.13*10^5 Pa, and V0 = 0.0235 m^3. Fig. 20-29 http://s1142.photobucket.com/albums/n603/bdoneski/?action=view&current=hrw7_20-29.gif" (a) Calculate the work done...
  16. N

    Calculate Work Done by Ideal Gas

    Homework Statement 1 mole of an ideal gas is at 9 atm pressure, occupies 1 L and has an internal energy of 474 J. The gas is first cooled at constant volume until its pressure is 1 atm. It is then allowed to expand at constant pressure until its volume is 7 L with an internal energy of 766...
  17. P

    No Work Done during Circular Motion

    Hi guys, :smile: Work Done = Force x Distance x cos of Theta - the angle between the Force and the Displacement Vector / direction of motion In Circular motion I know the force but I am given velocity. In order to prove that no work is done is it correct to say the following: If we have two...
  18. P

    How is acceleration = work done?

    Hi :smile: So, let's go straight to the point: a = v - u / t Kinetic Energy: 1/2 mv2 Ok, I understand that a acceleration, a change in velocity, will change the Kinetic Energy since v is part of the Kinetic energy equation. But acceleration is not simply a change in velocity. It is the rate...
  19. E

    How Is Net Work Calculated in a Cyclic Ideal Gas Process?

    Homework Statement An ideal gas follows the three-part process shown in the figure. At the completion of one full cycle, find the net work done by the system. Homework Equations W=P*deltaV; Total Work = Wab+Wbc+Wca A=1/2bh The Attempt at a Solution Work done from C to A is zero, because...
  20. D

    What is the work done by a radial force in this situation?

    Homework Statement http://img26.imageshack.us/i/1113001.jpg/ #11 Homework Equations C = 2πr w=fd The Attempt at a Solution it travels from point 1 to 2 so its half a circle so the distance is πR. πRF = w so i would guess its D. but the answer is A) zero. i do not know why...
  21. V

    How Much Work Is Done in Adiabatic Compression of Gas?

    Homework Statement When a volume 10^-3 m^3 of a certain gas at a pressure of 1 atm undergoes a reversible adiabatic compression to half its volume, its pressure rises by a factor of three. The internal energy of the gas is given by E=3PV, where P is the pressure and V is the volume. By making...
  22. I

    Work done by the torque on a pulley

    Homework Statement The pulley in the illustration is a uniform disk of mass 2.40 kg and radius 0.220 m. The block applies a constant torque to the pulley, which is free to rotate without friction, resulting in an angular acceleration of magnitude 0.180 rad/s2 for the pulley. As the block falls...
  23. Z

    Induced Electric Field work done

    Homework Statement In a cylindrical region of radius R, there exists a time varying magnetic field B such that dB/dt=k(>0) . A charged particle having charge q is placed at the point P at a distance d (> R) from its centre O. Now, the particle is moved in the direction perpendicular to OP (see...
  24. G

    Work done by force (Vector notation)

    Homework Statement How much work is done by a force= (2x)i N + (3)j N with x in meters, that moves a particle from a position (initial) = (2m)i + (3m)j to a position (final) = (-4m)i + (-3m)j? Answer: - 6 J Homework Equations Work = integral of Force The Attempt at a Solution...
  25. G

    Find Work Done on 230 kg Crate in 12 m Displacement

    Homework Statement A 230 kg crate hangs from the end of a rope of length L = 12.0 m. You push horizontally on the crate with a varying force to move it distance d = 4.00 m to the side (Fig. 7-43). (a) What is the magnitude of when the crate is in this final position? Figure...
  26. D

    Calculating Work Done by a Force on a Coin

    Homework Statement A coin slides over a frictionless plane and across an xy coordinate system from the origin to a point with xy coordinates (2.2 m, 6.1 m) while a constant force acts on it. The force has magnitude 8.2 N and is directed at a counterclockwise angle of 108° from the positive...
  27. N

    Find work done draining water from a tank

    Homework Statement A tank of water is 3m long and has a triangular cross section of height 1m and width at the top of 1m. How much work is done pumping the water to the top of the tank? The density of water is 1000kg/m3 and the gravitational constant g has value g m/s2 Homework Equations...
  28. B

    Calculating Work Done by a Variable Force in an Electric Elevator

    An electric elevator with a motor at the top has a cable weight 4.5 lb/ft. When the car is at the first floor, 198 ft of cable are paid out, and effectively 0 ft are out when the car is at the top floor. How much work does the motor do just lifting the cable when it takes the car from the first...
  29. P

    Calculating Water Pump Efficiency and Work Rate

    Hello, Was wondering if anybody could help with the following question as I am struggling, and this area is not my strong point. Note this is not homework purely self-study, out of curiosity to help me understand the subject area in more detail. In each minute a pump draws 2.4m^3 of water...
  30. C

    How Much Work Is Needed to Launch a Weather Monitor Into Space?

    Homework Statement How much work is done against gravity to fire a 7.2*10^2 kg weather monitor 120km into the air. Homework Equations Mass Earth = 5.98*10^24kg radius of Earth = 6.38 * 10^6 m Eg = -GMm/r delta Eg = Eg 2 - Eg 1 The Attempt at a Solution Eg1= -[(6.67*10^...
  31. Q

    Work done on an inclined slope?

    Homework Statement Imagine a block with mass m being pulled up a frictionless incline with upward angle theta by a rope with tension force T. The mass is pulled until another point of rest at a point distance d away from the original point (with d measured on the incline) and h measured on the...
  32. A

    Finding Work Done with Integration

    Homework Statement There's a cone with height 12 feet and radius 4 feet. It is filled with water to a depth of 9 feet. Find the work required to pump the water over the top. The density of water is 62.4lbs/ft^3 work=force*distance & force=volume*density The Attempt at a Solution...
  33. Y

    Calculating Work and Energy for a Cyclist Riding Up a Slope

    Homework Statement a cyclist rides up a steady slope for a distance of 1200m and rises 90m vertically as a result. the total mass of rider + cycle is 80kg a) assume a drag force of 10N opposing the motion(due to air resistance and friction), what Total Work must be output by the rider for...
  34. 5

    What is the force required and amount of work done to stop this motion?

    Homework Statement An object of mass 1200 kg rests at a height of 95 m above the ground on a roller coaster. After a series of inclined planes, repeately reaching a height of zero, (bumps and drops of the roller coaster) the roller coaster lays horizontal on the ground (height zero) for 7 m...
  35. N

    Thermodynamics gas work done question

    Homework Statement In the temperature range 310K and 330K the pressure of a non ideal gas is related to volume V and temperature T by P=(24.9 J/K) T/V− (0.00662 J/K^2)T^2/V. How much work is done by the gas if it's temperature is raised from 310K to 320K whilst pressure held constant...
  36. R

    Work done by string, friction, pulling mass up an inclined plane

    Homework Statement A block of mass 1.60 kg is pulled up a rough 30 degree incline at constant speed by a string parallel to the surface. The friction force on the block is 7.00 N. The incline is 4.00 m long and 2.00 m high. (1) How much gravitational potential energy did the block gain...
  37. J

    Work Done Problem: Solve for Total Work by 94.6 N Force

    Homework Statement A block is being slid along a rough surface by a force of 94.6 N forming an upward angle with the horizontal of 29 degrees. The mass of the block is 18.7 kg. It is displaced 70.6 m, and the coefficient of friction is .186 what is the total work done by the force...
  38. M

    Work done on a stationary bike

    Our local YMCA is putting on an indoor triathlon and I am trying to come up with a formula to help them determine the winner of the cycle segment. The indoor triathlon consists of a 10 minute pool swim, a 20 minute cycle on an indoor, stationary bike, and a 20 minute run on the treadmill. The...
  39. E

    Work in Pulley System: What is the Total Work Done on the 20.0-N Block?

    Homework Statement Two blocks are connected by a very light string passing over a massless and frictionless pulley (Figure ). The 20.0-N block moves 75.0cm to the right and the 12.0-N block moves 75.0cm downward. Find the total work done on 20.0-N block if there is no friction between the...
  40. A

    Work done for an adiabatic process

    Hi, In deriving the equation for adiabats : V^{\gamma}P = C. It is assumed that the work done during the process is W = -P \Delta V. But calculating the work done from V^{\gamma}P = C we obtain: W = \frac{C}{1-\gamma}\left[ V^{1-\gamma}_{f} - V^{1-\gamma}_{i} \right] . Also, i believe to...
  41. A

    Calculating Work Done by Force of Gravity on a 0.245 kg Ball

    Homework Statement A 0.245 kg ball is thrown straight up from 2.20 m above the ground. Its initial vertical speed is 12.40 m/s. A short time later, it hits the ground. Calculate the total work done by the force of gravity during that time. Homework Equations 1/2m(v initial)2 + mg(h...
  42. J

    How Much Work Was Done by the Pump to Drain a Flooded Basement?

    Homework Statement The floor of a basement in a house is 3.2m blow the grade of a window sill. If the Basement has flooded to a depth of 0.44m and the basement is 10.3m by 18.4m. If the water leaves the pipe at 2.4m/s, how much work was done by the pump. (Density of water is 1000 kg/m^3)...
  43. C

    Calculating Work Done for a Box on Horizontal Floor

    Homework Statement A box, whose weight is 182 kg, is drawn with constant speed 21 m along a horizontal concrete floor. The kinetic friction between the box and the floor is 0.58. (acceleration due to gravity, g = 9,81 m/s2). Homework Equations Calculate the work done when the box is drawn...
  44. X

    Why is Work Zero at Constant Volume?

    I am having a little trouble understanding this and I was wondering if I could get some help. I understand that work done at constant volume is zero because since the volume isn't changing, there is no movement on the boundaries and therefore no work. But it isn't coming out mathematically...
  45. E

    Net Work Done by an Accelerating Brick

    Homework Statement A 12 kg brick moves along an x axis. Its acceleration as a function of its position is shown in Fig. 7-37. What is the net work performed on the brick by the force causing the acceleration as the brick moves from x = 0 to x = 5.2 m...
  46. M

    Work done on a block on an inclined plane

    1. Homework Statement [/b] A block of weight mg sits on an inclined plane as shown. A force of magnitude F is applied to pull the block up the incline at constant speed. The coefficient of kinetic friction between the plane and the block is Mu. What is the total work done on the block by the...
  47. F

    How Is Work Calculated When Lifting an Object Vertically?

    Hello, I have a question that should be pretty simple, but I can struggling to understand: What determines the amount of work done in lifting a ball from one to two metres above the ground? I know that W=Fd and F=ma , so I would assume that the work done would equal m*a*d. Something...
  48. A

    What is the speed of the particle at x=3.8 m?

    A force acts on a particle of 1.6kg mass, the force is related to the position of the particle by F=0.5x^{3} Find the work done by the force as the particle moves from x=3.8 m to x=2.0 m. By plugging each value of x into the force equation I get that: F at 3.8 m = 27.436 N F at 2.0 m =...
  49. M

    Electrostatics - Work done by an electron

    The problem states: how much work is done in moving an electron from a distance of 1nm to a distance of 10nm away from a hydrogen nucleus? My attempt at the problem is using the W=\DeltaU=q\DeltaV. With this equation I would get a positive work. However, when I reason through the question, I...
  50. D

    Problem on work done in thermodynamics

    Homework Statement A paddle turns at 28.0 rad/s and exerts a torque of 16.0 Nm to stir the paint. Internal energy increase of 12.5kJ causes the temperature of the paint to increase by 1.00K. If there where no heat flow between the paint and the surroundings, what is the change in temperature...
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