Year 7 Science week 15 Movement in Space part 1.pptx

Year 7 Science Lesson

1. Lesson: Movement in Space Part 1 3. Be able to show the trend in planet orbit speeds with distance from the Sun . Objectives: 2. Be able to represent results in a suitable way and to understand that a bar graph is more suitable than a line graph 1. Be able to explain that gravity is the force that holds components of the Solar System in orbit around the sun

2. In your exercise books, list the names of the planets in order, starting with the one that is closest to the Sun Task 1 - Can you name the planets of our Solar System?

3. Do you need some help?

4. Task 1 - Can you name the planets of our Solar System? _ A _ _ H S _ _ U _ N _ A _ S U _ A _ _ S N _ P _ _ _ _ V _ _ _ S _ L _ _ O M _ R _ U _ _ E A R T H M E R C U R Y S A T U R N M A R S P L U T O U R A N U S J _ P _ _ _ R J U P I T E R N E P T U N E V E N U S

5. What order are the planets from the Sun? M y V ery E asy M ethod J ust S hows U s N ine P lanets Mnemonic P M V E M J S U N The Sun Nearest Furthest Mercury Venus Mars Jupiter Saturn Uranus Neptune Pluto Earth Solid Rock Large Gas Giants Dwarf Ice Planet

6. Task 2 – Where is the orbit of the Moon?

7. Task 2 - Position & Orbit of the Moon Orbit of Earth Orbit of Mars Orbit of Venus Mars Earth Venus Sun TASK Draw the moons orbit and put a dot where the moon could be. The diagram shows the orbits of Venus, Earth and Mars. The positions of the planets are shown Moon Orbit of Moon

8. The Sun and Its Gravity F rom our past lessons, what can you say about the gravity of large masses and the gravity of small masses? From all the bodies you can find in space, which body or object is having the greatest mass? So which will have the greatest gravity? Yes the Sun has a mass which is 330 000 times greater than that of the Earth and the gravity of the Sun is 270 N/kg How many times is the gravity of the Sun greater than that of the Earth? Yes, 27 times What holds all the planets together around the Sun? Gravity holds all planets together around the Sun Does the gravity of the Sun get stronger or weaker as the distance from the Sun increases? Now, the planet Neptune is 30 times further away from the Sun than the Earth. Will the gravity of the Sun on Neptune be stronger or weaker? Well, the mass of Neptune is about 17 times the mass of the Earth. So although the Sun’s gravity gets weaker, it is strong enough to hold Neptune in orbit.

9. Speeds of Planets and their Orbits in Space Looking at the images to the left, what is the shape of the orbits of the planet? Yes, circular , means shape of a circle So all planets move in a circle around the Sun, what causes the planets to turn? Yes the force of gravity acts on planets to keep them on orbit? The force of gravity from the Sun acting on planets is always in a particular direction. What is that direction? The direction is always towards the Sun What would happen to planets if there were no gravitational forces acting on them? The planets would travel off in a straight line into space The closer a planet is to the Sun, the stronger the gravity on it. Which of the planets will have the strongest pull from the Sun’s gravity? Mars On Earth, moving objects are slowed down by some kind of forces. What is the name of one of these forces Which of the planets will have the greatest speed? Mars, because the stronger the gravity on a planet, the greater its speed Air Resistance, caused by moving objects having to push particles in the air planet d irection of orbit d irection of force from the Sun’s gravity

10. Speeds of Planets and their Orbits in Space Does air resistance act in the direction to which an object moves or in the opposite direction? In opposite direction to the direction of motion Is it true that the faster the an objects moves, the greater the air resistance on the object? Is there air in space? Is the air particles in space? Yes No, there is no air and so no air particles in space What is the name given to a space where there are no particles? Vacuum If air resistance is responsible for slowing down and even stopping motion of objects on Earth, What will happen to motion of bodies in space? The objects will never slow down or stop planet d irection of orbit d irection of force from the Sun’s gravity So will the Earth and other planets ever slow down or stop moving? Since the Earth and other planets are in space, is there any air resistance acting against them? No No What is the only force acting on planets?

11. Activity: P lanet Speeds Learners Book Page 94 and 95 Use the materials given to you to do this activity When done Exchange your books with a classmate and correct their work

12. You have been given small pieces of paper with questions. Write down one thing you learnt in this lesson Write down one skill you used in this lesson Write down one thing you found difficult in this lesson