Recent content by navm1

got it. so i used x as 1/2 and got Rln(2). makes sense to me and seems to match my course material. I still don't quite understand why it asks for an entropy change of the system when they mix and when theyve mixed and the tap is shut so they can't mix any more. I am guessing the entropy change...

Homework Statement A bottle with volume v containing 1 mole of argon is next to a bottle of volume v with 1 mole of xenon. both are connected with a pipe and tap and are same temp and pressure. the tap is opened and they are allowed to mix. What is the total entropy change of the system? Once...

thank you. how come the emf and Ir are added together in this case and not subtracted if they are opposite? then when the motor stalls the total voltage of 120v is used in the equation? was it 8 before?

Homework Statement A series dc motor:[/B] A dc motor with its rotor and field coils connected in series has an internal resistance of 2.00 Ω. When running at full load on a 120-V line, it draws a current of 4.00 A. a) What is the emf in the rotor? b) What is the power delivered to the motor...

my mistake, that is one revolution so three should be 36431metres

v_0 in the z direction is 0 so z=1/2*((qE/m))t^2 = 1/2* ((1.6x10^-10)(5000))/1.673x10^-27)*(1.3x10^-4)^2 = 4041m = 4km ?

Thanks. For part b, if I use v_0t+1/2*((qE/m))t^2 as the position of the proton along the z direction. Then for part c I can calculate the period and then put '3T' into the equation I found in part b to find the particles position. Am I on the right track with this?

Homework Statement Homework Equations F=qE+qv x B The Attempt at a Solution The electric and magnetic fields are parallel, so the magnetic force will be in the j direction and the electrostatic force will be in the k direction. If the magnetic force was acting alone it would be cyclotron...

Also another quick related question, if I'm asked for the directional derivative in the positive x direction and calculated del-phi of a scalar function to be some (xi+yj) do I just plug numbers into the x component? edit: I worked out that if I think of that as a vector with components (1,0)...

Thanks. That has definitely helped me build a little more intuition for what I was doing

Am I to just integrate each component by its respective variable? I am not sure how to calculate ∇φ for a vector function edit: just by looking at the components I got x^2yz+x because the rest have x^2 still and there would only be a +1 if there had been a x there. not sure if there was a...

Homework Statement Prove that the vector field F = (2xyz + 1, x^2 z, x^2 y) is irrotational. Find the potential φ associated with F (i.e. find the function φ for which ∇φ = F). Homework EquationsThe Attempt at a Solution I figure for the first part I just calculate the curl, but for the...

Homework Statement Find the distance which an object moves in time t if it starts from rest and has an acceleration d^2x/dt^2 = ge^-kt. Show that for small t the result is approx "x=(gt^2)/2" and show that for very large t, the speed is approximately constant. the constant is called the...

makes sense. thanks haruspex

Homework Statement [/B] My question is regarding Part B of this problem, I have solved it but I'm wondering if there is another way to solve it since it says dtheta/dt and one of the hints I found online suggested that I use the chain rule. Homework Equations Q = mc(deltaT) Q/t = P The...