Recent content by etown

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    What is the Charge on the Capacitor in a Circuit After Switching Positions?

    Homework Statement The switch in the figure has been in position a for a long time. It is changed to position "b" at t=0s. What is the charge Q on the capacitor at t=50s? (zeros denote empty space in the circuit) |----(a)0000(b)--------- | |00000\00000000000000|...
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    Force between two point charges

    thanks!
  3. E

    Force between two point charges

    Homework Statement Two positive point charges are 4.60 cm apart. If the electric potential energy is 75.0 x 10^-6 J, what is the magnitude of the force between the two charges? Homework Equations U=kq/r (1) F=kqq/r^2 (2) The Attempt at a Solution So I tried using (1)...
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    How to Find the Half-Life of an Isotope from Decay Rate Measurements?

    Measurements of a certain isotope tell you that the decay rate decreases from 8339 decays/minute to 3037 decays/minute over a period of 4.50 days. What is the half-life T_1/2 of this isotope in days?I know that i have to relate the ratio of decay rates to the ratio of undecayed nuclei present at...