1. L

    Temperature function of a gas derivation help

    I cant quite figure out how the so-called temperature function of a gas equation is derived from equations 1-4 in the attachment(from Planck's treatise on thermodynamics). Anything that helps me understand how this is arrived at would d be much appreciated!
  2. L

    FRESNEL DIFFRACTION DERIVATION THAT est. the wave theory of light

    Fresnel derives a diffraction intensity equation by summating the interfering light waves' amplitudes, at the diffraction screen, using a line integral (equ 1). "Hence the intensity of the vibration at P resulting from all these small disturbances is { [ ʃ dz cos (π z2 (a + b) /...
  3. L

    Planck's blackbody derivation

    Why does Planck's energy element (hv) have the units of the kinetic energy yet light is massless?
  4. A

    Power of a rotor - derivation

    I'm trying to understand the equation P = 2(pi)TN/60, where T=torque, N=rpm... So far I understand: E = F.d = F.(2.pi.r)*(no. of revolutions) = 2T.pi.n And P = E/t = 2T.pi.n/t - but n/t is revolutions per second, so: P = 2T.pi.f f = rev/second This is where I'm having...
  5. F

    Derivation of Critical Angle

    Hi, I've derived the critical angle: n1*sin(x1) = n2*sin(x2) x1 is critical angle of incidence, call it C. x2 is refracted at 90 degrees, therefore sinx2 = 1 so you get sinC = n2/n1. However, in my syllabus it is written as sinC = 1/n Can someone please explain to me how...
  6. L

    Calculate a derivation of a the angular speed of a solid body

    I am practicing for a mechanics exam. Please find the problem and solution in the image: I am not able to reach the solution. The question is to derivate an expression of the angular speed to obtain the angular acceleration. The angular speed is a function of the rotation angle, so...
  7. T

    Derivation of Equations of Motion in Kinematics

  8. B

    Projectile Motion Derivation

    Problem When a ball reaches its maximum height, its speed is one-fourth the speed with which it was thrown. What was the launch angle? Concepts that I understand I understand that at the maximum height, the velocity of the ball only has a component in the x-direction, and I've made the...
  9. K

    Derivation of lorentz factor

    If you look at attachment I have a minkowski diagram showing a world line and corresponding time line (shown in orange). I decided to try and calculate length of line segment BC assuming that the ratio of AB to BC will give me gamma (the lorentz factor). I figure segment \overline{AB} = x_b -...
  10. K

    Derivation of Lagrangian

    I am working through the derivation of the lagrangian but don't get this step: \frac{\partial T}{\partial \dot{q}}=\sum_{i=1}^N m_i \mathbf{\dot{r}}_i \cdot \frac{\partial \mathbf{\dot{r}_i}}{\partial \dot{q}} =\sum_{i=1}^N m_i \mathbf{\dot{r}}_i \cdot \frac{\partial \mathbf{r}_i}{\partial q}...
  11. T

    equations in derivation of Roothaan's method computational schroedinger

    I don't get how they obtain the right side of (14) and (15) in th upload. Can anyone show how? Thanks! the full document is here if it is available for everyone at this link: file:///C:/Users/Tor/Downloads/Snow_JChemEd1972.pdf
  12. L

    Berouilli equation derivation

    In the first photo , the author wrote that the acceleration in steady flow is due to the change of velocity with position ... What does it mean ? Does it mean the Pressure force can act in different direction one is up the streamline , the another one is down the streamline ( refer to the photo...
  13. K

    Is this Shrodinger Equation derivation a it fishy?

    [Edit: Title should have read "Is this Shrodinger Equation derivation a bit fishy?" ] DrPhysicsA, on youtube, does great short mathematical derivations that I don't need 5 post graduate degrees to follow. But I kind of got to thinking about this:
  14. kelsiu

    Question about thermodynamic temperature derivation

    In deriving thermodynamic temperature scale, it uses the concept that heat transfer between two reservoirs is the function of the reservoirs' temperatures. i.e. Q1/Q2=Φ(T1,T2). And then further express that Φ(T1,T2)=ψ(T1)/ψ(T2). I have two questions. Is it a hidden assumption that the...
  15. L

    Geomertical optics- derivation of graph of (u+v) against u

    may i know how to derive the the sha[pe of graph and get the point of min (2f , 4f) ? i really have no idea how to get the shape of the graph and the min point.
  16. F

    Vibrating String in 2D Wave Equation Derivation

    I am looking for the derivation of the wave equation for a vibrating string in 2D. Most derivations I've seen assume that each particle in the string only changes in the y direction. I am looking for a derivation where movements in the x direction are also possible.
  17. U

    Don't understand their derivation of precession frequency of this gyroscope?

    How did they get this precession frequency of this gyroscope? To summarize: 1. The solenoid is supplied with an AC voltage. 2. Produces an AC magnetic field out of the page 3. Exerts an AC magnetic force on the Nb-Plate that's placed just outside of one end of the solenoid 4. There...
  18. F

    Derivation for rotating cylinder

    The vase problem has now been solved dthank you kind ser ia ma a little drunk and high right now haha!!!
  19. N

    Physics Derivation Problems?

    Where can I find examples of Physics derivation problems for my newtonian physics class? I would also like examples with answers. Topics I'm looking for are motion, momentum, force (including springs and tension), and energy. No calculus based physics examples. Some examples include the two...
  20. R

    Taylor derivation of three-point forward difference formula

    I have a test early next week on using the Taylor series. Does the attached derivation look correct and is the error term correct? Thank you all for your help so far, especially Dr. Phil.