Escape Velocity

• What is escape velocity?

  The minimum speed to escape a gravitational field
• What factors determine escape velocity?

  Mass and radius of the object creating the field
• What is the definition of escape velocity?

  Minimum speed to escape a gravitational field
• How does escape velocity relate to different masses in the same gravitational field?

  It is the same for all masses in that field
• When does an object reach escape velocity?

  When kinetic energy equals gravitational potential energy
• How is escape velocity calculated?

  By equating kinetic and gravitational potential energy
• What is the equation for escape velocity?

  • $v =$$\sqrt{\frac{2 \times G \times M}{r}}$
  • Where:
  • $G$ = Newton's Gravitational Constant
  • $M$ = mass of the object to escape from
  • $r$ = distance from the center of mass
• What happens to mass in the escape velocity equation?

  It cancels on both sides of the equation
• Why do rockets not need to achieve escape velocity to reach orbit?

  They receive continuous energy from fuel and thrust
• What is the difference between escape velocity and the velocity needed to leave a planet?

  Escape velocity is for leaving the gravitational field
• What is the escape velocity at the surface of the Moon?

  Calculated based on its mass and density
• What should be avoided when defining escape velocity?

  • Avoid terms like 'gravity' or 'gravitational pull'
  • Refer to it as the gravitational field instead
• What is the relationship between escape velocity and gravitational fields?

  Escape velocity is specific to gravitational fields
• Is the escape velocity the same for all objects on Earth?

  Yes, it is the same for all objects
• What does the escape velocity equation derive from?

  Equating kinetic energy and gravitational potential energy