### About

### For Teachers

### Translations

Code | Language | Translator | Run | |
---|---|---|---|---|

### Software Requirements

Android | iOS | Windows | MacOS | |

with best with | Chrome | Chrome | Chrome | Chrome |

support full-screen? | Yes. Chrome/Opera No. Firefox/ Samsung Internet | Not yet | Yes | Yes |

cannot work on | some mobile browser that don't understand JavaScript such as..... | cannot work on Internet Explorer 9 and below |

### Credits

Juan M. Aguirregabiria (http://tp.lc.ehu.es/jma.html); lookang; tina

### end faq

### Sample Learning Goals

Students should be able to:

- show an understanding of the concept of a gravitational field as an example of field of force and define the gravitational field strength at a point as the gravitational force exerted per unit mass placed at that point.
- recognise the analogy between certain qualitative and quantitative aspects of gravitational and electric fields.
- recall and use Newton’s law of gravitation in the form \( |F| = \frac{GM_{1}M_{2}}{r^{2}} \)
- derive, from Newton’s law of gravitation and the definition of gravitational field strength, the equation g=GMr2for the gravitational field strength of a point mass.
- recall and apply the equation g=GMr2 for the gravitational field strength of a point mass to new situations or to solve related problems.
- show an understanding that near the surface of the Earth g is approximately constant and equal to the acceleration of free fall.
- define the gravitational potential at a point as the work done per unit mass in bringing a small test mass from infinity to that point.
- solve problems using the equationϕ=-GMrfor the gravitational potential in the field of a point mass.
- analyse circular orbits in inverse square law fields by relating the gravitational force to the centripetal acceleration it causes.
- show an understanding of geostationary orbits and their application.

### For Teachers

### Video

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