I need some help with my homework questions. Can someone please explain these to
ID: 1284133 • Letter: I
Question
I need some help with my homework questions. Can someone please explain these to me? :) Thanks!
Some people think that shuttle astronauts are "weightless" because they are "beyond the pull of Earth's gravity." In fact, this is completely untrue. (m/s^2)
(a) What is the magnitude of the gravitational field in the vicinity of a shuttle orbit? A shuttle orbit is about 439.6 km above the ground.
m/s2
(b) Given the answer in Part (a), explain why shuttle astronauts suffer from adverse biological affects such as muscle atrophy even though they are not actually "weightless"?
- What is the magnitude of the gravitational field at the surface of a neutron star whose mass is 1.64 times the mass of the Sun and whose radius is 10.2 km? (m/s^2)
- that the Earth retained its present mass but its radius was somehow compressed to three-fifths its present radius. What would be the value of g, the acceleration due to gravity, at the surface of this new, compact planet? (m/s^2)
Explanation / Answer
The formula for calculating gravitational field strength is:
g = GM/r^2
Where G is the gravitational constant, M is the mass of the body being considered (in this case the Earth), and r is the distance from it's centre.
g = 6.673*10^-11 * 5.9742*10^24 / (6378100+439600)^2
g =8.576
g = 8.576 m/s^2 to three significant figures.
Although there is gravity, and therefore they are not technically weightless, they are in constant freefall, along with everything around them. This is the same effect as being in a weightless environment.