A geostationary satellite

Geostationaryjava3DsideviewA geostationary satellite is a satellite in geostationary orbit, with an orbital period the same as the Earth’s rotation period. The geostationary orbit is a circular orbit directly above the Earth’s equator.

How high above the Earth’s surface must the geostationary satellite be placed into orbit?

Continue reading

Advertisements

How long would it take to fall through the center of the Earth?

450px-9_daughters_hole
We have a hole that leads straight through the center of the Earth. We neglect air resistance and assume that the Earth has uniform density ρ. How long would it take to fall through the center of the Earth and reach the other side of the planet?

Continue reading

If the solar system were reduced

Solar System (artist's impression) If all the linear dimensions of the solar system were reduced in some proportion, then what will be the length of Earth’s year?

 

Continue reading

How long does it take for the Earth to reach the Sun?

Earth
If we stopped the Earth in orbit then how long does it take for the Earth to reach the Sun?

Continue reading

Why is the Earth Round?

EarthNasaThe Earth, the Moon, the Sun, the stars and the planets round or spherical, because they have a very large mass. Their own gravitational force aims to give them the shape of a sphere.

Continue reading

 Where does a bullet fall if someone shoots it straight up?

rifleAt the North or South pole a bullet will land at the same spot, but at the equator …
Continue reading

When does the Sky become Space?

ShuttleIf we are flying higher and higher it is meant to fly with greater and greater speeds. A speed, above a certain altitude, could be bigger than the circular orbital speed at that altitude.
Continue reading