ESCAPE VELOCITY

1
ESCAPE VELOCITY

• ANDREW ROBINSON
• 2nd Project
• PHYS 001

2
What is Escape Velocity?

• Commonly referred to as the speed and object
  needs to break free from a gravitational field.
• But in a scientific sense, it is speed where the
  kinetic energy of an object is equal to the
  gravitational potential energy

3
Escape Velocity Equation

• Ug -Gm1m2/r

4
What causes Escape Velocity

• Escape Velocity is a cause of the principle of
  conservation of energy
• For a given gravitational potential at any point,
  the escape velocity is simply the speed needed by
  an object without propulsion to break free of a
  gravitational pull

5
More on Escape Velocity

• Escape Velocity is actually a speed, not a
  velocity
• Because there is no direction defined
• An object can escape a gravitational field in any
  direction
• By this thinking, Escape Velocity is a scalar
  quantity and not a vector

6
More on Escape Velocity

• Escape Velocity is independent of the mass of the
  object
• What differs is the energy required to accelerate
  the object
• The energy for an object is defined by GMm/r,
  where G is the gravitational constant, m is the
  mass of the object, M is the mass of Earth,and r
  is the Earths radius

7
More on Escape Velocity

• The escape velocity relative to the surface of a
  rotating body depends on the direction the
  escaping object travels
• Surface velocity decreases according to the
  cosine of latitude, and as a result, many space
  facilities are built close to the equator

8
Black Holes

• Black holes are Red Giant stars that have gone
  Supernova and collapsed in on themselves
• Their gravitational potential is so strong that
  not even light can reach the escape velocity
  required to get out

9
Black Hole pulling in gas from nearby planet
10
Orbit

• Any object that reaches escape velocity, but does
  not travel in a straight line will form an orbit
• It will take a parabolic shape
• The center of mass will be the planet the object
  escaped from
• If gravity is the only force, the velocity of the
  object at any point on its orbit will equal its
  escape velocity due to the conservation of energy

11
Impact

• People are fascinated by space travel and rockets
• Escape Velocity is vital for creating the orbits
  for satellites used by GPS, weather, and other
  agencies
• During the exploration of the solar system, the
  Voyager probes had to reach escape velocities
  greater than that of the Sun to get beyond Pluto
  and out into deep space
• Eventually, humanity will have to leave Earth,
  and will have to calculate the escape velocity
  required to reach their new home