Kinematics and Dynamics Flashcards
Dot product
When multiplying two vectors to get a scalar
A•B=|A||B|cosθ
Cross product
When multiplying two vectors to get vector
AxB= |A||B|sinθ
Vector Addition
The resultant vector of A+B is the same as B+A
Vector Subtraction
Resultant vector of A-B has same magnitude as B-A but oriented in the opposite direction
Displacement
A change in position in space. It is a vector quantity, with magnitude and direction
Velocity (m/s)
It is a vector. It’s magnitude is measured as the rate of change of displacement in a given unit of time. Direction is the same as the direction of the displacement.
Speed
Rate of actual distance traveled in a given unit of time.
Force (N=(Kg•m)/s^2)
A vector quantity, experienced as a push or pull on objects, and can exist on objects that are not touching
Gravitational Constant (G)
6.67x10^-11 (N•m^2)/kg^2
Static Friction
Exists between stationary object and the surface it rests.
0<=fs<=μsN
Always larger then kinetic friction, and dissipates as you get an object in motion
Kinetic Friction
Exists between a sliding object and the surface over which the object slides. Always present when there is sliding of two surfaces, so always constant unlike static friction.
fx=μkN
Mass
Measure of a bodies inertia, the amount of matter in the object. A scalar quantity; independent of gravity.
Weight
Measure is gravitational force on an objects mass. It is a vector because it is a force.
Acceleration (m/s^2)
The rate of change of velocity that an object experienced as a result of some applied force. A vector quantity
Newton’s first law
A body at rest or in motion with constant velocity will remain that way unless a net force acts upon it. Law of Inertia.
Fnet=ma=0
Newtons Second Law
An object of mass m will accelerate when the vector sum of the forces results in some nonzero resultant force vector.
Fnet=ma
Newtons Third Law
To every action, there is always an opposed but equal reaction. Law of action and reaction.
Linear motion
Objects velocity and acceleration are along the line of motion so the pathway of the moving object continues along a straight line
Kinematics (no displacement)
v=vo+at
Kinematics (no final velocity)
x= vot + (at^2)/2
Kinematics (no time)
v^2=vo^2+2ax
Kinematics (no acceleration)
x=vt
Projectile motion
Motion that follows a path along two dimensions.
Incline planes (force components)
Fg parallel=mgsinθ
Fg perpendicular=mgcosθ
Circular Motion
Occurs when forces cause an object to move in a circular pathway.
Fc=(mv^2)/r
Uniform circular motion
Motion that contains instantaneous velocity vector tangent to the circular paths with centripetal force pointing radially inward. Constant speed/velocity
Translational motion
Occurs when forces cause an object to move without any rotation
Rotational motion
When forces are applied against an object in such a way as to cause the object to rotate around a fixed pivot point (fulcrum)
Torque
Generates rotational motion
τ=rxF=rFsinθ
Clockwise rotation=negative
Counterclockwise rotation=positive
