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Force & Motion. NOTES 4: F = ma (Newton’s 2 nd ). NEWTON’S 2 nd LAW STATES…. The acceleration of an object is dependent upon the force acting upon the object and the mass of the object. F=ma (force equals mass times acceleration). MEASURING FORCE.
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Force & Motion NOTES 4: F = ma (Newton’s 2nd)
NEWTON’S 2nd LAW STATES… • The acceleration of an object is dependent upon the force acting upon the object and the mass of the object. • F=ma • (force equals mass times acceleration)
MEASURING FORCE 4 types of measurement for Newton’s 2nd law: • ACCELERATION • m/s2 • Newton • Mass vs. Weight
ACCELERATION • The rate of change of the speed or direction of a moving object with respect to time. (AKA deceleration)
m/s2 • Unit used to express accleration(a) • meters per second per second
NEWTON (N) • the SI (standard international) unit for force • Equal to: • 1 kg x 1m/s2
MASS vs. WEIGHT MASS WEIGHT • The vertical force exerted by a mass as a result of gravity • WEIGHT is dependent on the amount of gravity. • Gravity is equal at all places around the Earth, so we often use weight as a shorthand to describe the property of mass. • The amount of matter in an object • MASS does not change – if I am made up of 1 million atoms, I will always be made up of 1 million atoms. Even if… I weigh less on the Earth than I do on the moon even though my mass is the same.
OKAY, SO… • F = ma • HOW DOES FORCE AFFECT ACCELERATION?? • The more force applied to an object, the more acceleration the object will experience. • WHERE DOES MASS FIT IN? • The greater the mass of an object, the less acceleration it will experience under the same force • HOW DOES MASS EFFECT FORCE (the amount of push/pull)? • The higher the mass of an object, the more force the object can apply.
EXAMPLE ONE If I hit a baseball as hard as I can, the ball accelerates more than if I were trying to bunt the ball. WHY? I’m applying MORE FORCE!!
EXAMPLE TWO If I hit a baseball and a bowling ball with the same force, the bowling ball will go slower than the baseball. WHY? The bowling ball has MORE MASS and therefore ACCELERATES LESS!!
EXAMPLE THREE If I hit a baseball with a 24oz. bat and a 32 oz. bat, the ball will go farther with the 32 oz. bat. WHY? The 32 oz. bat has MORE MASS and can apply MORE FORCE!!