1. P

    A Theoretical status of the Landauer Principle

    I am interested to understand the current theoretical status of Landauer's Principle and related ideas. I am looking for key papers and results in the subject. I will highlight one key paper. An improved Landauer principle with finite-size corrections Abstract: Landauerʼs principle relates...
  2. FQVBSina

    I Question about net work and displacement

    I know that by physics definition if displacement is zero, work is zero. However, if I push an object 5 m to the east, and then move to the other side of the object and push it 5 m back to the west. I think in this case I have always done positive work on the object and hence the total work...
  3. hagopbul

    Physics Jobs during a PhD

    Hello all: I am asking for your personal experience , did you were able to work normally with your PhD studies ? What kind of work ? Is it easier with theoretical PhD or an experimental one ? Best H.B.
  4. J

    Energy and non-conservative forces

    I feel like it would go on the side of the energy the object has where it starts - an object dropped off a cliff would be modeled U - W = K but an object thrown upwards from ground level would be K - W = U. I am not sure though.
  5. E

    How do adapters work? (SATA to USB, or VGA to HDMI)

    Does adapters (exp: SATA to USB or VGA to hdmi) work with special softwares for conversion or are they only electronic circuits which gets and directs input signals to correct output pins?
  6. O

    B Confused by the relationship of work and kinetic energy

    So the equation for work is W = F * s F = m * a, so W = m * a * s Transferring this to units of measurement gives us: J = kg * m * s-2 * m Or simplified: J = kg * m2 * s-2 Transferring back to units of quantity: W = m * v2 How can that be correct? Obviously Ekin = 1/2 * m * v2. Where did that...
  7. patric44

    What is the direction of work in this figure?

    iam not sure of the direction of work , is it positive becouse pulleys change the direction of the force ? or is it negative because of the arrow that indicates the direction of acceleration ??!
  8. R

    B How to work out Joules needed to perform work

    Hello all! First post here, and I apologize in advance if this question belongs elsewhere- I'll learn as I go. I am interested in knowing more about energy and performing work. In particular, if I have an object I would like to lift, how much energy I need to expend to do that. Take for...
  9. T

    Internal energy in ideal gas

    I have the definition of change in internal energy. $$ \Delta U = Q - W $$ I can get the work by $$ W = \int_{V_1}^{V_2} p dV = p \Delta V $$ however the pressure isn't constant so this wont do. ## W ## is work done by the gas and ## Q ## is amount of heat energy brought into the system. I'm...
  10. Emilyyyyyyyyy

    Calculate the impact force when falling from a height

    To find vx vx = dx/t = 3.86 m/1.5 s= 2.573 m/s To find Ek Ek = ½mvx²= ½(79.4)(2.573)²= 262.8 J W = FnetΔd Fnet = 262.8 J/ 3.86 m = 68 N He hits him with a force of 68N
  11. M

    How far does the block slide? (work, spring, incline)

    1. Homework Statement The system is released from rest with no slack in the cable and with the spring stretched 225 mm. Determine the distance s traveled by the 3.2-kg cart before it comes to rest (a) if m approaches zero and (b) if m = 2.5 kg. Assume no mechanical interference and no friction...
  12. Avatrin

    Job Skills Github for data science

    Hi I have the educational background to do a few jobs I have seen posted as "data scientist" or "data engineer". However, I keep getting told that to get a job like that with my background, in mathematics, I need to post code examples on Github. However, I always feel like my ideas are either...
  13. Akash47

    Emptying a well using a pump

    1. Homework Statement A well has a diameter of 6 m and a height of 15 m.2/3 of volume of the well is filled with water.A pump can vacate 1/3 of volume of water from the well in 7 minutes 20 seconds.What is the power of the pump? 2. Homework Equations W=mgh, P=W/t 3. The Attempt at a Solution...
  14. Curtiss Oakley

    Problem involving energy/motion

    1. Homework Statement A ball of mass m=0.300 kg is connected by a strong massless rod of length L = 0.800 m to a pivot and held in place with the rod vertical. A wind exerts constant force F to the right on the ball as shown below. The ball is released from rest. The wind makes it swing up to...
  15. Isolde Wilde

    DIY Stirling engine project

    hello, I had made an DIY alpha type Stirling engine for my physics project and now I have to write an report about the relationship between the heat given to the engine and the motion of the wheel. I had searched a lot about Stirling engines and I learned about work, energy, efficiency...
  16. Romain Nzebele

    How to calculate the work done

    1. Homework Statement A sledge loaded with bricks has a total mass of 18.0 kg and is pulled at constant speed by a rope inclined at 20.0° above the horizontal. The sledge moves a distance of 20.0 m on a horizontal surface. The coefficient of kinetic friction between the sledge and surface is...
  17. Burhan Uddin

    Calculating the work done using a line integral

    1. Homework Statement a) A point charge + q is placed at the origin. By explicitly calculating the relevant line integral, determine how much external work must be done to bring another point charge + q from infinity to the point r2= aŷ ? Consider the difference between external work and...
  18. C

    Calculating the final speed w/ work & friction

    The problem is asking me to find the final speed of a 1100 kg car traveling at 24 m/s through 18m of mud, where the resistive force on the car is 17000 N. I don't actually know how to go about doing this, so any pointers in the right direction would be super helpful.
  19. L

    B Total Work versus External Work

    Is there an important difference between total work and external work? My knowledge would be that total work a.k.a. net work on a system would be equal to the change in kinetic energy of that system and equal to the line integral of the net force on the system dotted with the differential...
  20. S

    Determining Work Done by a Person on a Luggage

    I'm trying to determine the work done by a person as they pull a luggage up a ramp. The ramp has a height of 5 m and the distance the person walks up is 20 m. The weight of the bag is also 10 kg. I am trying to compare the work done by pulling the luggage up a ramp to carrying an equally heavy...
  21. I

    B Does greater acceleration result in more work done?

    Work W done by moving the object with force F for distance s is W = Fs. When I move the same object the same distance but with twice the acceleration, does the work done gets also doubled? By F=ma, doubling the acceleration yields m*2*a = 2F -> 2Fs = 2W. I've mostly read, that if I want to...
  22. T

    Kinetic energy & Conservation of energy

    1. Homework Statement You are driving with your car (of total mass: 1.2tonnes) with a speed of v=50km/h, until you see an obstacle. a) What is the kinetic energy of the car? b) When you start to brake, there is still 15m until the obstacle. What must be the size of the friction coefficient...
  23. T

    Finding the Work of a spring and friction with a changing angle

    1. Homework Statement We shot a projectile with mass ##m## and velocity ##v_0## with angle ##\phi## it collide with a box with mass ##M## at the maximum height of its path. Then, they both start to move with another speed. (We define ##t=0## at this time) (Completely Inelastic Collision). The...
  24. T

    Question about the Work-Kinetic Energy Theorem - Pulling a cart

    1. Homework Statement Question from Fundamentals of Physics (Halliday, Resnick, Walker) This figure below shows a cord attached to a cart that can slide along a frictionless horizontal rail aligned along an x axis. The left end of the cord is pulled over a pulley, of negligible mass and...
  25. J

    Speed or turning point using energy

    1. Homework Statement Please look at the attached screenshot. This problem is really confusing for me and I can't seem to make much sense out of it. 2. Homework Equations Ei = Ef 3. The Attempt at a Solution As you can see, I did get (a). (The other checkmarks, I guessed — there were...
  26. C

    I Force fields in curvilinear coordinate systems

    I am trying to solve problems where I calculate work do to force along paths in cylindrical and spherical coordinates. I can do almost by rote the problems in Cartesian: given a force ##\vec{F} = f(x,y,z)\hat{x} + g(x,y,z)\hat{y}+ h(x,y,z)\hat{z}## I can parametricize my some curve ##\gamma...
  27. S

    Find the speed of an object using work and energy

    1. Homework Statement An object with mass 100 kg moved in outer space. When it was at location < 9,-24,-4 > its speed was 3.5 m/s. A single constant force < 250,400,-170 > N acted on the object while the object moved from location < 9,-24,-4 > m to location < 15,-17,-8 > m. Then a different...
  28. S

    Calculate the work done moving a crate

    1. Homework Statement you push a box out of a carpeted room and along a hallway with a waxed linoleum floor. While pushing the crate 2 m out of the room you exert a force of 34 N; while pushing it 6 m along the hallway you exert a force of 13 N. To slow it down you exert a force of 40 N through...
  29. arturo

    Can we find work done on this particle, and if not, what are we missing?

    1. Homework Statement A force varies with time according to the expression F=aΔt, where a = 2.0 N/s. From this information, can you determine the work done on a particle that experienced this force over a displacement of 0.50 m? 2. Homework Equations W = F*d Vf = Vo + aΔt F = ma 3. The...
  30. Dave Mata

    Adiabatic Reversible Compression of a Solid

    1. Homework Statement Derive an expression for the change of temperature of a solid material that is compressed adiabatically and reversible in terms of physical quantities. (The second part of this problem is: The pressure on a block of iron is increased by 1000 atm adiabatically and...