Comet Orbit Astrophyiscs question

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SUMMARY

The discussion centers on calculating the mean potential energy (PE) and kinetic energy (KE) of a comet at perihelion, where it is 1 AU from the sun and traveling at 200 km/s. The kinetic energy is calculated using the formula K = 0.5mv², yielding a value of 8.8 x 10²¹ J. The potential energy is derived from U = -GMm/r, resulting in -1.5 x 10⁴ J. The total energy is 8.79 x 10²¹ J, confirming that the virial theorem is satisfied, as the sum of KE and PE equals twice the total energy.

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Homework Statement


"Supposing that at perihelion a comet is 1 Au from the sun and its speed at that point is 200km/s( in a frame of referance in which sun is stationary). Find its mean PE and KE to one sig digit. Does it satisfy the virial theorem?


Homework Equations


K= .5mv^2
U=-GMm/r
Virial theorem:


The Attempt at a Solution



I know how to calculate U and K, and I know that at perihelion the V is at max, but will the K and U I find be the mean?
 
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Also, I am not sure how to calculate the Virial theorem. Any help would be greatly appreciated. K= .5mv^2 = .5(2.2x10^14)(200x10^3)^2 = 8.8x10^21 JU=-GMm/r = -(6.67x10^-11)(2.2x10^14)/1 = -1.5x10^4 JThe Virial theorem states that the sum of the kinetic and potential energies of a system are equal to twice the total energy. In this case, the total energy = K + U = 8.8x10^21 + (-1.5x10^4) = 8.8x10^21 - 1.5x10^4 = 8.79x10^21 JTherefore, the Virial theorem is satisfied.
 

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