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Gravity: A Force of Attraction. Chapter 1, section 4 Cohick. Effects of Gravity on Matter. Why is leaping in space easier than leaping on Earth?. Yes--Gravity!!. Gravity is the force of attraction between objects due to their masses.
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Gravity: A Force of Attraction Chapter 1, section 4 Cohick
Effects of Gravity on Matter Why is leaping in space easier than leaping on Earth? Yes--Gravity!!
Gravity is the force of attraction between objects due to their masses. The force of gravity can change the motion of an object by changing its speed, direction, or both.
The Effects of Gravity on Matter REVIEW • All matter has mass. • Gravity is the result of mass. • Therefore all matter is affected by gravity. • That is, all objects experience an attraction toward all other objects.
Newton and the Study of Gravity 1665; Sir Isaac Newton, a British scientist, realized unbalanced forces are needed to change an objects motion. An unbalanced force on the apple is what makes it fall.
Unbalanced forces keep the moon moving circularly around Earth. • This force is called GRAVITY
The Birth of a Law • Newton summarized his ideas about gravity in a law now know as the law of universal gravitation. • It describes the relationship between gravitational force, mass, and distance.
Why do astronauts “bounce” on the moon? YES--The moon has less mass
Weight is a measure of gravitational force • Gravity is the force of attraction between objects. • Weight is a measure of the gravitational force on an object. • (Weight usually refers to G.F. on Earth)
The difference between Weight and Mass • Weight changes with gravitational force. • Mass is the amount of matter in an object.
Units of Weight and Mass Newton • The SI unit for force is? • Gravity is a? • Weight is a measure of ? • So, weight is measured in ? • The SI unit for mass is? • On Earth 100g weight ~ 1 Newton. force gravity Newtons Kilogram Kg (gram) g
Assignment • Page 25 • # 3,4,5,6,7,8,& 10 • In complete sentences.