Q.Halley's comet is in an elliptic orbit about the sun. The orbit eccentricity is 0.967 and the period is 76 years. Taking the mass of the sun to be [tex] 2 \times 10^30 kg[/tex] abd the usual value of G, determine the max and min distances of the comet from the sun.(adsbygoogle = window.adsbygoogle || []).push({});

Now i've worked out teh answers but they differ from the values i've found on the net,(my guess is the value I've used for the solar mass isn't very accurate!) so would you mind taking a second to have a look at what i've done to see if i'm correct.

A.

using...

[tex]a=( \frac{GM_{\odot}T^2}{4 \Pi ^2})^\frac{1}{3} [/tex]

i got

[tex]a= \sqrt[3]{ \frac{ (6.67 \times 10^-11 )( 2 \times 10^30 )( 2.4 \times 10^9)^2}{4 \Pi^2}}

= 2.01 \times 10^9 m

[/tex]

from

[tex]e= \frac{a-R_{min}}{a}

[/tex]

[tex]

R_{min} = 6.633\times1 0^6

[/tex]

then to get R_max i used

[tex]

R_{max} = 2a - R_{min}

= (2)(2.01\times10^9) - (6.633\times 10^6)

= 2.666\times 10^{16} m

[/tex]

the problem is i`ve found a value for R_min = 8.9x10^10 and R_max = 5.3x10^12 !

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# Homework Help: Aphelion/Perihelion of Halleys comet

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