Knowing that the acceleration of gravity on the moon is 0.166 times that on Earth and that the moon’s radius is 0.273 times the radius of the Earth, find the escape speed for a projectile leaving the surface of the moon.

To escape the gravity of the moon the kinetic energy an object must have must be equal to or greater than the gravitational potential energy of the moon. So set the kinetic and gravitational potential energy equal and solve for the escape velocity. Substitute in values that relate the expression to values of the earth. Then evaluate the expression.
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