Gravitational Potential energy question

AI Thread Summary
The discussion centers on calculating various energy values for a satellite in orbit, including gravitational potential energy, kinetic energy, binding energy, and the energy required for escape velocity. The gravitational potential energy was calculated as -3.13 x 10^10 J. There is confusion regarding the radius needed for kinetic energy calculations, with the Earth’s radius of 6000 km mentioned. Participants clarify that the Schwarzschild Radius is not applicable to this problem. The focus remains on correctly applying the relevant equations to find the required values.
MasterAsia
Messages
1
Reaction score
0

Homework Statement


a 5.00 x 10^2 kg satelilite is in circular orbit 2.00 x 10^2 km above Earth's surface. calculate

a) gravitaional potential energy which i got, which is -3.13 x 10^10 J
b) kinetic energy of the satellite
c) binding energy of satellite
d) the percentage increase in launching energy required for the satellite to escape earth

Homework Equations



2GM/c^2

Eg = - GMem/re

The Attempt at a Solution



v = sqroot GM/r for the velocity then using the equation 1/2mv^2 to get the Ek, but i don't know how to get the radius so i can plug it into the Ek equation.
 
Physics news on Phys.org
The Earth has a radius of 6000 km.
 
How did you get the gravitational potential without knowing the radius?
2GM/c^2
That's Schwarzschild Radius. That is not a relevant equation for this problem.
 
Thread 'Variable mass system : water sprayed into a moving container'
Starting with the mass considerations #m(t)# is mass of water #M_{c}# mass of container and #M(t)# mass of total system $$M(t) = M_{C} + m(t)$$ $$\Rightarrow \frac{dM(t)}{dt} = \frac{dm(t)}{dt}$$ $$P_i = Mv + u \, dm$$ $$P_f = (M + dm)(v + dv)$$ $$\Delta P = M \, dv + (v - u) \, dm$$ $$F = \frac{dP}{dt} = M \frac{dv}{dt} + (v - u) \frac{dm}{dt}$$ $$F = u \frac{dm}{dt} = \rho A u^2$$ from conservation of momentum , the cannon recoils with the same force which it applies. $$\quad \frac{dm}{dt}...
TL;DR Summary: I came across this question from a Sri Lankan A-level textbook. Question - An ice cube with a length of 10 cm is immersed in water at 0 °C. An observer observes the ice cube from the water, and it seems to be 7.75 cm long. If the refractive index of water is 4/3, find the height of the ice cube immersed in the water. I could not understand how the apparent height of the ice cube in the water depends on the height of the ice cube immersed in the water. Does anyone have an...
Back
Top