Forces Flashcards
What is Newton’s first law?
Says that an object at rest, stays at rest and an object in motion stays in motion with a constant velocity unless acted upon by an unbalanced force
What is Newton’s second law?
Says The acceleration of an object Is directly proportional to the net force on it and inversely proportional to its mass
More force, more acceleration
Bigger mass, harder to accelerate
What is Newton’s third law?
Say that for every action, there is an equal but opposite reaction
What is the formula associated with Newton’s second law?
Net force = mass X acceleration
If velocity is constant what is the net force and acceleration?
0
If you are given a weight in Newton’s how do you find it in kilograms?
You divided the weight in Newton’s by the acceleration due to gravity
What is the weight of an object measured in Newton’s called?
Force of gravity
Where is the normal force always pointed (direction)?
The normal force is always out of, and perpendicular to the surface
Do all forces perpendicular to the surface cancel?
Yes
What is kinetic friction?
Is the force of friction generated when one object slides across another object
What is the equation for finding the force of kinetic friction?
Force of friction = coefficient of kinetic friction (u) X normal force
Is the coefficient of friction always the same If two objects are the same?
Yes it doesn’t change
What direction is friction always?
Opposite to the direction of the sliding object
What is static friction?
The friction between two stationary objects
What is the equation for static friction and what does it give us?
Force of static friction (Ffs) = coefficient of static friction (Us) X normal force (Fn)
It gives us the maximum value of force of friction or the minimum force amount of force that would be required to start moving
If an object has a force of static friction of 20 N, what is the minimum amount of force required for it to start moving?
20.00001 N or so
