Issac Newton figured this out i believe........ the question is......?

Question

How fast does a cannon ball have to go to escape gravity/reach outer space?

(this is friggen 8th grade science)

Answer 1

The simplest way of deriving the formula for escape velocity is to use conservation of energy, thus: in order to escape, an object must have at least as much kinetic energy as the increase of potential energy required to move to infinite height.

Defined a bit more formally, "escape velocity" is the initial speed required to go from an initial point in a gravitational potential field to infinity with a residual velocity of zero, relative to the field. Conversely, an object starting at rest and at infinity, dropping towards the attracting mass, would reach its surface moving at the escape velocity. In common usage, the initial point is on the surface of a planet or moon. On the surface of the Earth, the escape velocity is about 11.2 kilometres per second. However, at 9,000 km altitude in "space," it is slightly less than 7.1 km/s.

The escape velocity from the surface of a rotating body depends on direction in which the escaping body travels. For example, as the Earth's rotational velocity is 465 m/s to the east at the equator, a rocket launched tangentially from the Earth's equator to the east requires an initial velocity of about 10.735 km/s relative to earth to escape whereas a rocket launched tangentially from the Earth's equator to the west requires an initial velocity of about 11.665 km/s relative to earth. The surface velocity decreases with the cosine of the geographic latitude, so space launch facilities are often located as close to the equator as feasible, e.g. the American Cape Canaveral in Florida and the European Centre Spatial Guyanais, only 5 degrees from the equator in Guyana.

Answer 2

To reach low earth orbit it needs to achieve 17,500 miles per hour. To escape Earth completely it needs to leave at 25,000 miles per hour or faster. Of course, it slows down as it fights gravity to leave; the 25,000 miles per hour is just the initial speed starting from the surface.

Answer 3

Hi. The escape velocity plus an amount of extra energy to make up for air friction losses. 7 miles per second.

Answer 4

About 7-8 miles per second.

Answer 5

Roughly 25,000 mph--also called the escape velocity of earth.

Calculating this was srtandard fare for sophopmore university students in my day (1961). Maybe 8th graders do it now......?

Answer 6

Either 25,000 mph or 2,500.I beleive the first one, but friends tell me other wise.

Answer 7

he was a lot smarter than i was cause that is over my head!