CH2-مضغوط 2_removed.pdf

Vectors Force and Law of Inertia Force, work and power Kinetic energy and potential energy  Vectors Vector  a quantity that requires both magnitude and direction Examples: Velocity, Force, Acceleration, Displacement, W Scalar Sca...

Vectors Force and Law of Inertia Force, work and power Kinetic energy and potential energy  Vectors Vector  a quantity that requires both magnitude and direction Examples: Velocity, Force, Acceleration, Displacement, W Scalar Scalar  a quantity that can be described by magnitude only So, it is represented by just a number. Differentiate between Displacement vs Distance Examples: Speed, Mass, Temperature, Time, Distance  Resultant Of Vectors Resultant: The sum of two or more vectors – For vectors in the same direction: add arithmetically. F1 = 6 N F2=3 N R=9N = – For vectors in opposite directions: subtract arithmetically. F1 = 6 N F2=3 N R=3N =  Resultant Of Vectors – Two vectors at right angles to each other: use Pythagorean Theorem: R2 = X2 + Y2. R=?N 80 N Differentiate between 60 N Displacement vs Distance – Two vectors that don’t act in the same or opposite direction: use Parallelogram rule. F2 R F2 F1  Vectors Vector components Vertical and horizontal components of a vector are perpendicular to each other Determined by resolution. EXAMPLES: 69. If an airplane heading north with speed vP = 400 km/h faces a westbound wind (‫ )ريح نحو الغرب‬of speed vA = 300 km/h, the resultant velocity of the plane is: A. 500 km/h, north-west ✓ B. 700 km/h, north-east C. 500 km/h, north-east D. 700 km/h, north-west  Linear Motion Speed  scalar quantity requiring magnitude only to describe how fast a body is. INSTANTANEOUS SPEED: The speed at any instant of time EXAMPLE:  Velocity Velocity  vector quantity requiring magnitude & direction. It describes how fast and in what direction. CONSTANT VELOCITY: Means motion in straight line at a constant speed. CHANGING VELOCITY: If either the speed or the direction (or both) changes, then the velocity changes.  Acceleration Acceleration  Is the change in velocity per unit time. Dimensions: Length/Time2 ([L]/[T2]) ; Units: m/s2, km/h2, ft/min2, etc … EXAMPLE:  Acceleration Acceleration Acceleration Acceleration EXAMPLE: EXAMPLE: Deceleration Deceleration Deceleration EXAMPLE: Acceleration as a vector: geometrical representation Acceleration + – Uniformly ‫ بشكل موحد‬accelerated motion and free fall Characterized by the constant acceleration  its direction & magnitude are unchanging. EXAMPLES: ACCELERATED MOTION: Equations for motion in straight line with constant acceleration: Displacement is a vector pointing from the initial to the final position and with magnitude equals the shortest distance between the initial and final position EXAMPLE: EXAMPLE: