Physics Unit 2: Dynamics
T/F and Multiple Choice Aid:
● Regularly times pictures of a ball falling at terminal speed (freefall) will have even
spacing
● Compared to slow-moving objects, fast-moving objects experience more air resistance
● Compared to small objects, big objects experience more air resistance
● The magnitude of gravitational field strength is equal to the magnitude of the
gravitational acceleration
● A runner pushing off starting blocks is an example of static friction making an object
move
● Terminal speed occurs when the force of gravity equals the air resistance acting on an
object
● An object in freefall solely has the force of gravity acting on it
● The force of air resistance on an object depends on several factors, including the
object’s cross-sectional area
● When an object is sliding, it experiences a lesser magnitude of friction force than when it
is stationary
● Usually friction does not depend on the contact area, but rubber is an exception
● Gravitational force is responsible for the interactions during particle transformations
● Not all forces require objects to be in contact and can instead act at a distance eg:
electromagnetic forces
● Two blocks, at 4.0 kg and 5.0 kg, are suspended from the ceiling by a piece of string, the
tension in the string is 88 N
● If you push a box across a floor in the direction E 40° N, the friction force will act in the
direction W 40° S
● The weak nuclear force is involved when protons and neutrons transform into other
particles
● The slope of a net force versus acceleration diagram represents mass
● Air resistance acts opposite to the direction of motion if there is no wind
Force is a vector (has magnitude and direction)
Newton’s Three Laws of Motion:
1) An object will not change its motion unless a force acts on it.
2) The force on an object is equal to its mass times its acceleration.
3) When two objects interact, they apply forces to each other of equal magnitude in
opposite directions.
Mass: Amount of matter in an object (remains constant)
Weight: Force of gravity acting on an object (changes relative to location)
T/F and Multiple Choice Aid:
● Regularly times pictures of a ball falling at terminal speed (freefall) will have even
spacing
● Compared to slow-moving objects, fast-moving objects experience more air resistance
● Compared to small objects, big objects experience more air resistance
● The magnitude of gravitational field strength is equal to the magnitude of the
gravitational acceleration
● A runner pushing off starting blocks is an example of static friction making an object
move
● Terminal speed occurs when the force of gravity equals the air resistance acting on an
object
● An object in freefall solely has the force of gravity acting on it
● The force of air resistance on an object depends on several factors, including the
object’s cross-sectional area
● When an object is sliding, it experiences a lesser magnitude of friction force than when it
is stationary
● Usually friction does not depend on the contact area, but rubber is an exception
● Gravitational force is responsible for the interactions during particle transformations
● Not all forces require objects to be in contact and can instead act at a distance eg:
electromagnetic forces
● Two blocks, at 4.0 kg and 5.0 kg, are suspended from the ceiling by a piece of string, the
tension in the string is 88 N
● If you push a box across a floor in the direction E 40° N, the friction force will act in the
direction W 40° S
● The weak nuclear force is involved when protons and neutrons transform into other
particles
● The slope of a net force versus acceleration diagram represents mass
● Air resistance acts opposite to the direction of motion if there is no wind
Force is a vector (has magnitude and direction)
Newton’s Three Laws of Motion:
1) An object will not change its motion unless a force acts on it.
2) The force on an object is equal to its mass times its acceleration.
3) When two objects interact, they apply forces to each other of equal magnitude in
opposite directions.
Mass: Amount of matter in an object (remains constant)
Weight: Force of gravity acting on an object (changes relative to location)
