2. 3. The solar system is held together by gravity

3. Define Newton's Law of Universal Gravitation (NOT the law) Describe a gravitational field in the region surrounding a massive object in terms of its effects on other masses in it ( the law) Present information and use available evidence to discuss the factors affecting the strength of the gravitational force Solve problems and analyse information using

4. Discuss the importance of Newton‘s Law of Universal Gravitation in understanding and calculating the motion of satellites remember r = r E + altitude So high altitude (e.g. geostationary) orbits are lower velocity and low altitude (e.g. low Earth) orbits are higher velocity

6. Identify that a slingshot effect can be provided by planets for space probes Planetary swing-by to pick up speed by gaining K.E. from the planet (which consequently loses a bit of speed) Interaction behaves as an elastic collision ViVi vivi Conservation of momentum and conservation of kinetic energy gives v f = v i + 2V i VfVf N.B. this is the maximum result and will be less if not head-on interaction 10 1 satellite approaches planet at relative velocity of 11 so it will bounce off at 11 relative to planet 21 11 relative to the planet is 21 relative to the sun