Survey

* Your assessment is very important for improving the work of artificial intelligence, which forms the content of this project

Document related concepts

Centripetal force wikipedia, lookup

Equivalence principle wikipedia, lookup

Work (physics) wikipedia, lookup

Classical central-force problem wikipedia, lookup

Newton's laws of motion wikipedia, lookup

Classical mechanics wikipedia, lookup

Fundamental interaction wikipedia, lookup

Newton's theorem of revolving orbits wikipedia, lookup

Relativistic mechanics wikipedia, lookup

Transcript

Gravity The force of attraction between objects that is due to their masses All matter has mass, so all matter experiences gravity. The Law of Universal Gravitation Stated by Sir Isaac Newton (1642-1727) “All objects in the universe attract each other through gravitational force . The size of the force depends on the masses of the objects and the distance between them.” Mass vs. Weight Mass is the amount of matter in an object. (Measured in grams or kilograms) Weight is the measure of the gravitational force exerted on an object. (Measured in Newtons) Why do we weight less on the moon? -Because the moon has less mass than the earth. How many Newtons do you weigh? 1. Convert lbs. to kg (Weight in pounds X 0.4536) 2. Convert kg to Newtons (Weight in kg X 9.8) Ex. 190 lbs X 0.4536 = 86.18 kg 86.18 kg X 9.8 = 844.60 N Acceleration due to gravity 9.8 m/s/s – the rate at which all objects fall towards earth (ignoring air resistance.) Terminal Velocity Is the point at which a falling object stops accelerating and begins to fall at a constant speed. If there were no atmosphere there would be no air resistance. (That’s why a feather and a rock would land at the same time if dropped on the moon.)