Can't really figure out where to start. Any help would be appreciated.(adsbygoogle = window.adsbygoogle || []).push({});

1. The problem statement, all variables and given/known data

A 575 kg satellite is in a circular orbit at an altitude of 550 km above the Earth's surface. Because of air friction, the satellite eventually falls to the Earth's surface, where it hits the ground with a speed of 2.10 km/s. How much energy was transformed to internal energy by means of friction?

2. Relevant equations

E = -1/2 G Ms Me / r

v = 2 pi r / T

E = - G Me Ms / Re + d

M = mass

R = radius

3. The attempt at a solution

ok so 575kg, 550000 m above earths surface, falls at 2100 m/s

5.97 x 10^24 kg is earths mass (Me)

6378100 for earth radius (Re)

Ms is mass of satelite

G is constant

so for Ek = 1/2mv^2

= 0.5*575*2100^2

= 1267875 kJ

E = - G Me Ms / Re + d

= (6.67 x 10^-11)(5.97 x 10^24)(575) / (6378100 + 550000)

= -3.305 x 10^10

so do I substract E in orbit by Ek at crash (E - Ek)??

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# Satellite orbits and energy

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