Stage 3 Forces & Magnetism Comprehension: Gravity PDF

STAGE 3 Unit focus: Forces And Magnetism Text focus: Information Text Gravity Gravity is one of the most important forces in the universe. It was gravity that pulled the material...

STAGE 3 Unit focus: Forces And Magnetism Text focus: Information Text Gravity Gravity is one of the most important forces in the universe. It was gravity that pulled the material together in the early stages of the universe to create planets. It’s what keeps you pinned to the ground now. Despite that, it isn’t a very strong force at all. You prove this every time you stand up. If gravity on Earth was stronger, then you wouldn’t be able to lift your body up. All of your blood would rush to your feet, and you wouldn’t last long at all. When you jump, you overcome gravity altogether! If you had strong enough legs (alright, they’d need to be superhumanly strong), you’d be able to jump into space. It might surprise you to know that everything in the universe has its own gravity. Even you! You might not realise it, but you are pulling objects towards you as you sit there reading this. Unfortunately, the strength of your gravity is linked to how much mass you have. Unless you are prepared to eat enough to grow to the size of a country, you are unlikely to suddenly find spoons sticking to you! The strength of gravity is also linked to how close something is to the object. The gravity of the sun is significantly stronger than that of Earth. We are so far away from it that the force is very weak for us. If we got too much closer, we would be crushed by the force. However, the sun’s gravity is incredibly important. It is just strong enough to keep the Earth in orbit around it. This is what gives us our years and makes sure life can survive. Without it, the Earth would drift off into space! Our moon is another object that relies on gravity. The Earth’s gravitational pull keeps the moon in orbit. The Moon also creates gravity. Believe it or not, the Moon’s gravity pulls against the water on Earth. A ding ro Rea und all resources ©2022 Literacy Shed e um C u r r ic ul Th http://www.literacyshedplus.com This is what creates tides and is why the sea moves in and out when you visit the seaside. This has a strange effect. The Moon’s gravity causes the water on Earth to bulge. When the Earth spins, some of the energy goes into these bulges, which means that gravity is slightly weaker where the Moon is. This means that the Moon is slowly moving away from the Earth! It gets about 4cm further away each year! SUMMARY FOCUS 1. How did gravity help to create our universe? 2. How does the Moon’s gravity affect your holiday? 3. Why is the Moon’s gravity making it float away? 4. Summarise why we aren’t all pulled into the sun. VIPERS QUESTIONS V In the first paragraph, which word means “trapped”? V Which word means that the sun’s gravity is a lot stronger than Earth’s? R True or false: The Moon’s gravity is what keeps it in the Earth’s orbit. R True or false: The sun’s gravity is what keeps the Earth orbiting the sun. R How far away does the Moon drift each year? all resources ©2022 Literacy Shed http://www.literacyshedplus.com