Recent content by con31773

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    Problem on entropy change and specific heat capacity

    It turns out It wasn't a typo, the C here was the heat transfer per unit temperature (multiple of C and M), something I was not familiar with. As a result the the question becomes much simpler, just being the sum of the two entropy change (block and lake) Your help was much appreciated :)
  2. C

    Problem on entropy change and specific heat capacity

    Calculate the change in entropy of the Universe as a result of the following operations: (a) A copper block of mass 0.4kg and thermal capacity 150JK-1 at 100◦C is placed in a lake at 10◦C. dS=dQ/T dQ=mCdT Tried simply combining these equations and integrating to find change of entropy of...
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    Solve Kinematics Problem: Subway Train, Unbanked Curve, 15° Angle

    Well the centrifugal force should point in the opposite direction as the centripetal force, which always points to the center of the circle, therefore, it points in the direction the strap has been displaced. Asides from gravity and the force experienced due to the turning effect, I can't think...
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    Solve Kinematics Problem: Subway Train, Unbanked Curve, 15° Angle

    A subway train rounds an unbanked curve at 67km/h. A passenger, hanging onto a strap notices an adjacent strap is unused and makes an angle of 15° to the vertical. What is the radius of the turn? Relation of sines, opposite and hypotenuse of a right triangle. Opposite...
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    Trouble with electric force question

    Oops. Check what you got for r for q(1/3) Haha, thanks very much. Could not find my mistake at all.
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    Trouble with electric force question

    Homework Statement I'm having a little trouble with an electric force question I have been working on. It seems simple, but my answer keeps coming out incorrect. Using the graph, deduce the electric force vector on charge q3 by q1/2. In case it is not clear, q3 lies on point (2,2)...
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