A new planet MPSM, Mystery Planet of Spartan Men, is discovered following the orbital path of the Mystery Planet of Amazon Women. The gravitational field of the MPSM is measured during a satellite fly-by as 1.33 m/s2 at a distance of 5 planetary radii from the center of MPSM. What is the expected strength of the planet's gravity on its surface?

Explanation:

The strength of the gravitational field at a certain distance from the centre of a planet is given by:

where:

G is the gravitational constant

M is the mass of the planet

The equation can be rewritten as follows:

The term on the right is a constant term, so we can write:

where

is the gravitational field strength at distance

is the gravitational field strength at distance

Here we have:

When (the distance is 5 planetary radii), the gravitational field strength is

where R is the radius of the planet.

Instead at the surface

And so the strength of the gravitational field at the surface is:

1/0.14nm = 10^10/1.4 a lot

answer would be letter choice (a),   a ball resting on a shelf. would be another example of potential energy   >   stored energy > not moving.

a ball spinning on a finger   >   kinetic energy > moving energy

a ball rolling on the ground   >   kinetic energy   > moving energy

a   ball flying through the air   > kinetic energy   >   moving energy

hope that                                         : )