Recent content by Vir

  1. V

    Specific heat capacity of metal

    I thought gases and liquids had the same properties? The question specifically asks me to figure it out using these data.
  2. V

    Specific heat capacity of metal

    Homework Statement I have 1.5 kgs of silicon with temperature 40 degrees celsius. It is dropped into 3 kgs of water holding temperature 25 degrees celsius. The system is heat isolated from the environment and the final temperature of the system is 26.2 degrees celsius. I need to find the...
  3. V

    Integration constants, gravitational potential of sphere

    So I checked my book: The potential dV(x) at P from dM, that is now a small part of the ring, at distance S is given by: \begin{equation} dV(x) = \frac{-GdM}{S} \end{equation} \begin{equation} dM = \frac{M}{2 \pi R}Rd \theta \end{equation} So \begin{equation} V(x) = \frac{-GM}{2 \pi...
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    Integration constants, gravitational potential of sphere

    I don't know. My integral gives me the right answer for R>r: \begin{equation} V(r>R) = \frac{-GM}{2rR} \int_{r-R}^{r+R} ds \end{equation} Simplifies to: \begin{equation} V(r>R) = \frac{-GM}{r} \end{equation} I think the point is that when r<R then the rings both to the left and right of P...
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    Integration constants, gravitational potential of sphere

    Right. So what do I do with this?
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    Integration constants, gravitational potential of sphere

    Then I don't know. You asked about the magnitude of the remaining force, isn't that the horizontal component of the total force?
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    Integration constants, gravitational potential of sphere

    That would depend on the mass at P right? In any case it's \begin{equation} F = -\frac{GMm}{(r-R Cos \theta)} \end{equation}
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    Integration constants, gravitational potential of sphere

    Yea, ok. I was thinking since each point on the circle has a point on the opposite side where the perpendicular component of the forces would cancel out the net force would be parallell to the axis through the center of the circle and P. Not so?
  9. V

    Integration constants, gravitational potential of sphere

    When the ring is to the right of P the force points left, and vice versa.
  10. V

    Integration constants, gravitational potential of sphere

    Ok. So \begin{equation} dV(r<R) = \frac{-GdM}{S} \end{equation} \begin{equation} dM = \frac{M}{4\pi R^2}d \theta R Sin \theta R 2 \pi \end{equation} \begin{equation} dM = \frac{M}{2}Sin \theta d \theta \end{equation} \begin{equation} S = \sqrt{R^2+r^2-2Rr Cos \theta} \end{equation}...
  11. V

    Integration constants, gravitational potential of sphere

    Yes, a hollow sphere. I'm integrating small circles of the surface of the sphere. I guess this image describes it well.
  12. V

    Integration constants, gravitational potential of sphere

    I'm trying to arrive at the gravitational potential at a distance r < radius of sphere(R). The integral is \begin{equation} V(r<R) = \int \frac{-GM}{2rR}ds, \end{equation} but I'm not sure how to select my integration limits.
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    Integration constants, gravitational potential of sphere

    Homework Statement So I'm calculating the gravitational potential of a sphere at at point P. R = radius of sphere, r = distance from center of sphere to point P. I'm looking at two scenarios; r > R (1) and r < R (2). So I have the following integral: \begin{equation} V(r) = \int...
  14. V

    Angular velocity of a ball after change of direction

    Thank you for pointing this out, as it was the part I was missing. The new velocity vector is at a distance R from my reference point, which gives me the equation: \begin{equation} m R \cos θ V_0+ Iω_0 = mRV_1 + Iω_1 \end{equation} which simplifies to \begin{equation} ω_1 =...
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    Angular velocity of a ball after change of direction

    So, as the ball touches the incline, the angle between the two contact points is θ which gives me \begin{equation} x = R - R cos θ. \end{equation} wR = v I'm not exactly sure what you mean. The velocity is at an angle θ of the horizontal.
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