Recent content by sagardip

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    Second Order Differential Nonhomogeneous Equation

    And one more thing, the roots of your auxiliary equation are 1 and -4 respectively.
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    Second Order Differential Nonhomogeneous Equation

    And welcome to Physics Forums...
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    Second Order Differential Nonhomogeneous Equation

    Hii. Method of undetermined coefficients is sometimes lengthy but it sure does give the correct particular integral. As u have already written the rough Yp,what u have to do now is just replace it for y in the original equation and compare the coefficients of (e^4t)t^2,(e^4t)t and e^4t on both...
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    Interesting problem, I almost got it right.

    Actually it is possible that u haven't understood Gauss's law properly.In cylindrical type of charge distribution we generally take a cylindrical gaussian surface mainly because the electric field is perpendicular to the curved surface of the cylinder and so it helps with the integration of...
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    Solving Atwood's Machine: Find Accel & Time for 60 cm

    If you know the acceleration of a body and if the acceleration is constant can you not find the distance covered in t seconds.If u can then put the value of the distance i.e 60 cm in the equation and solve for t.
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    I just don't understand this Spring - ElectroStatic problem

    and the limits are from 0 to L because the x in the integration is just the extention or the compression in the spring.Here x=0 represents the equilibrium position where no external force is required to keep the body in a state of rest.
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    I just don't understand this Spring - ElectroStatic problem

    Potential energy is the work done by an external agent in moving a body slowly from the point of zero potential to the given point.Lets consider the two cases of compression and extension of a spring. In case of compression the spring exerts an outward force on the body so as to push it towards...
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    I just don't understand this Spring - ElectroStatic problem

    To flyingpig. What the solution requires is the use of Conservation of energy which states that if no external force acts on the given system then the total energy of the system remains the same. Here by total energy we mean the kinetic and the potential energies of the system. Now in case of...
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    How Is Potential Calculated in a Non-Central Charge Within a Grounded Cube?

    The potential of the cube is zero. So try the method of images to set up a system of charges due to which the potential of the cube is zero.See if that works
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    Prove if a^2 = 4 (mod 8) then a = 2 (mod 8)

    To all those who said that the proposition is wrong here is an example 10^2=100=4(mod8) and 10=2(mod8)
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    Prove if a^2 = 4 (mod 8) then a = 2 (mod 8)

    the theorem must be if a=b(mod n) then a^2=b^2(mod n)
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    Prove if a^2 = 4 (mod 8) then a = 2 (mod 8)

    Then it is correct
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    Prove if a^2 = 4 (mod 8) then a = 2 (mod 8)

    sorry i am wrong. If a^2=4(mod8) then obviously a=2,-2(mod8). so in your question -2 should be mentioned
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    Prove if a^2 = 4 (mod 8) then a = 2 (mod 8)

    the given conjecture is wrong as for any positive integer a we have a=0,1,2,3,4,-3,-2,-1(mod8) now squaring both sides we get a^2=0,1,4(mod8) . See there is no remainder 2
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    How Does Pressure Change with Altitude?

    see ,the change in pressure from bottom to top of the slab (dP) is equal to the pressure due to the weight of the slab.If you can figure this out then by writing out the equation, dP/dz can be easily solved and the answer comes out to be density of slab times g.