Science Lesson 3 How Does Gravity Affect Motion

Science Lesson 3: How Does Gravity Affect Motion? (page 64)

What is Gravity? • Gravity is a force of attraction between objects • Gravity is not only the force of attraction between objects and the Earth • Earth’s gravity is the force that keeps us down

Difference Between Mass and Weight Mass Weight It is the amount of matter found in an object It is the amount of force that gravity exerts on an object DOES NOT change from a planet to another CHANGES from planet to another Measured using a balance or scale Measured using an instrument called a spring balance SI unit is Kg SI unit is Newton (N)

How to Calculate Weight • To calculate weight, we use the equation: W=mxg Where: - W is Weight and it is expressed in Newton (N) - m is mass and it is expressed in Kg - g is gravity and it is expressed in N/Kg

Gravity Between Things • Gravity between things is the force of attraction between them • As Earth is pulling objects towards it, the objects are trying to pull Earth towards them (pairs of forces) • The force that wins usually is that done by the bigger object (the one that has more mass) • This is why we can’t pull Earth towards us; because it is more massive

Check Out These Links • https: //www. youtube. com/watch? v=Kw 51 Ki. Z hm 0 I • https: //www. youtube. com/watch? v=Y 8 T 8 Rouh. PA • https: //www. youtube. com/watch? v=1 y 3 Cl. Ny PRlg