Physics Exam 1

Physics Exam 1

1. Chapter 2 Motion, forces, and Newton's Laws

   • Motion
     • acceleration
       • a = v / t
     • position
     • velocity
       • velocity is a vector quantity,the magnitude of velocity is called speed.
       • Vave = delta x / delta t
       • average velocity and instantaneous velocity
     • Newton's Law
       • Newton's First Law: If the total force acting on an object is zero, the object will maintain its velocity forever.
       • Newton's Second Law: In many situations, several different forces act on an object simultaneously. the total force on the object is the sum of these individual forces. The acceleration of an object with mass m is given by: a = F / m.
       • When one object exerts a force on a second object, the second object exerts a force of the same magnitude and opposite direction on the first object.
         • all action come in action-reaction pairs.

2. Chapter 3: Forces and Motion in One Dimension

   • Part 1: constant acc. equations of motion, normal forces and weight, free body diagrams
     • Motion Along a Line
       • (Vfx)=(Vix) + (Ax)(T)
       • X= (Vix)(T) + (1/2) (Ax)(T)^2
       • (Vfx)^2= (Vix)^2 + (2)(Ax)(X)
     • Normal Force
       • Acts perpendicularly to the plane of contact
       • Apparent Weight= Normal Force
     • Free Body Diagram
       • Used for analysis using Newton's 2nd Law
     • Friction
       • Opposes the Motion
       • Kinetic Friction: F(friction)= (coefficient of kinetic friction) x N (normal force)
       • Static Friction: F (friction)= less than/ equal to= (coefficient of static friction) x N (normal force)
   • Part 2: free fall motion, Newton's 2nd Law applications
     • Free fall motion
       • any object which once projected or dropped continues in motion by its own inertia and is influenced only by the down force of gravity
       • object always has acceleration of gravity: 9.8 m/s^2
     • Tension
       • the ideal "cord" has zero mass, does not stretch, and tension is the same throughout the cord

3. Chapter 4

   • Ch4.1 static
     • ΣF(F-net)=ma
     • When forces are balanced their is no acceleration in the system
       • this is called static equilibrium
       • Which also means if there is no acceleration the is no un-balanced force F-net=0
   • Projectile Motion
     • X-component of velocity is always constant in projectile motion unless friction force is present.
     • The Y-component of velocity is always zero at its peak hieght
       • Always acted on by gravity if going up (negative acceleration) if going down (positive acceleration)
     • Range: is the total distances the object can cover in the X-direction
       • can be calculated by taking the X-component of the velocity and multiplying it by 2x the time it takes an object to reach its peach in (not including height differences or dead drops)
   • Tension force
     • A=(m2-m1)g/m1+m2