Write an Expression for the X Component of the Final Displacement in Terms of the Given Quantities

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Scalars quantities: are quantities that are fully described by a magnitude alone.

Vectors quantities are quantities that are fully described by both a magnitude and a direction.

Quantity	Category
a. 5 m	SCALAR
b. 30 m/sec, East	VECTOR
c. 5 mi., North	VECTOR
d. 20 degrees Celsius	SCALAR

Distance is a scalar quantity, which refers to "how much ground an object has covered" during its motion.

A boy walks 150 meters due east and then turns around and walks 30 meters due west. The boy walked a distance of 180 METERS

Displacement is a vector quantity, which refers to "how far out of place an object is"; it is the object's change in position. Straight line from start to finish.

A boy walks 150 meters due east and then turns around and walks 30 meters due west.

The boy's displacement is              120 METERS EAST

The Resultant: SUM OF TWO OR MORE VECTORS

A motorboat traveling 4 m/s, East encounters a current traveling 3.0 m/s, North.

RESULTANT = 5 M/S NORTH EAST

Analytical Vector Addition

X'S ADD WITH X'S (+EAST + - WEST)

Y'S ADD WITH Y'S (+NORTH + -SOUTH)

RESULTANT = √ Ax total ² + Aytotal ²

A motorboat traveling 6 m/s, North encounters a current traveling 3.8 m/s, South. What is the resultant velocity of the motorboat?

 RES = 2.2 m/s north

A motorboat traveling 4 m/s, East encounters a current traveling 7.0 m/s, North. Determine the resultant.

RES = 8.06 m/s north east

Vector Components Any vector directed at an angle to the horizontal can be broken down into its two components.

Ax = A Cos theta

Ay = A Sin theta

A motorcycle stunt person traveling 37 m/s jumps off a ramp at an angle of 35 degrees to the horizontal. Determine the horizontal and vertical components of the motorcycles velocity.

          AX = 30.31 m/s  AY = 21.22 m/s

Forces

Applied Force: PUSH OR A PULL ON AN OBJECT

WEIGHT: W = (MASS) * ( GRAVITY)

Normal Force: The normal force is the support force.  N = (-W)

Friction Force: ALWAYS OPPOSITE MOTION FRIC = COEFFICIENT * NORMAL STATIC FRICTION IS THE FRICTION THAT MUST BE OVERCOME TO GET AN OBJECT INTO MOTION. KINETIC FRICTION IS THE FRICTION THAT MUST BE AT LEAST MATCHED TO KEEP AN OBJECT IN MOTION. COEFFICIENT OF FRICTION DEPENDS ON THE TWO SURFACED IN CONTACT. STATIC FRIC ≥ KINETIC FRIC

Air Resistance Force ALWAYS OPPOSITE MOTION

Free-Body Diagrams Free-body diagrams are diagrams used to show the relative magnitude and direction of all forces acting upon an object in a given situation

Fnet: Is the unbalanced force that is causing the acceleration

Fxnet:

sum of forces in the x direction

Fynet:

sum of forces in the y direction

Inertia : Inertia depends on mass.

Inertia = the resistance an object has to a change in its state of motion.

MORE MASS = MORE INERTIA = MORE ABILITY TO RESIST CHANGE IN MOTION FROM AN UNBALANCED FORCE.

Newton's First Law Inertia at rest tends to stay at rest and an inertia moving with a constant velocity will continue to move at a constant velocity unless acted upon by an unbalanced force.

YOU DO NOT NEED A FORCE TO KEEP AN OBJECT IN MOTION YOU NEED A FORCE TO CHANGE AN OBJECTS MOTION.

A 2-kg object is moving horizontally with a speed of 4 m/s. How much net force is required to keep the object moving with the same speed and in the same direction?

NONE

Speed is a scalar quantity, which refers to "how fast an object is moving."

SPEED = DISTANCE/TIME

While on vacation, Lisa Carr traveled a total distance of 440 miles. Her trip took 8 hours. What was her average speed? SPEED = 55 MILES/HR

Velocity is a vector quantity, which refers to "the rate at which an object changes its position."  SPEED WITH DIRECTION

The task of describing the direction of the velocity vector is easy! The direction of the velocity vector is simply the same as the direction that an object is moving.

ALL GRAPHS IN PHYSICS COME FROM A FORMULA:

2 OF THE VARIABLES WILL BE ON THE X / Y AXIS.  THE 3^RD VARIABLE REPRESENTS THE SLOPE.

STRAIGHT LINES MEAN CONSTANT (WHAT EVER THE SLOPE IS REPRESENTING)

CURVED LINE MEAN CHANGING (WHAT EVER THE SLOPE IS REPRESENTING)

POSITIVE SLOPE MEANS POSITIVE (WHAT EVER THE SLOPE IS REPRESENTING)

NEGATIVE SLOPE MEANS NEGATIVE (WHAT EVER THE SLOPE IS REPRESENTING)

Constant Velocity Positive Velocity	Positive Velocity Changing Velocity (acceleration)

Rightward (+) Constant Velocity	Leftward (-) Constant Velocity

Determining the slope SLOPE = -3 m/s

Newton's Second Law The acceleration of an object as produced by a net force is directly proportional to the magnitude of the net force, in the same direction as the net force, +

and inversely proportional to the mass of the object.

Unbalanced forces cause acceleration and they are always in the same direction.

F_net = m * a

What acceleration will result when a 12-N net force is applied to a 3-kg object? A 6-kg object?

                        Acc = 4 m/s²                  Acc = 2 m/s²

A net force of 16 N causes a mass to accelerate at the rate of 5 m/s². Determine the mass.

                        Mass = 3.2 kg

An object is accelerating at 2 m/s². If the net force is tripled and the mass of the object is doubled, what is the new acceleration?

                        Acc = 3 m/s²

An applied force of 20 N is used to accelerate an object to the right across a frictional surface. The object encounters 10 N of friction. Use the diagram to determine the normal force, the net force, the coefficient of friction (µ) between the object and the surface, the mass, and the acceleration of the object. (Neglect air resistance.)

N = +100 N

M = 10.19 kg

Fnet = 10 N right

Acc = .98 m/s² right

u = .1

Acceleration is a vector quantity, which is defined as "the rate at which an object changes its velocity." An object is accelerating if it is changing its velocity.

The acceleration of any object is calculated using the equation

Since acceleration is a vector quantity, it will always have a direction associated with it. The direction of the acceleration vector depends on two things:

• whether the object is speeding up or slowing down
• whether the object is moving in the + or - direction

The general is:

If an object is slowing down, then its acceleration is in the opposite direction of its motion.

If an object is moving in the positive direction and slowing down, then its velocity is _positive_ and its acceleration is _negative_.

Renatta Oyle is driving rightward (+ direction) at 30 m/s when she suddenly slows down at a constant rate of acceleration to a rest position in 5 seconds.  Determine her acceleration.

                        Acc = -6  m/s²

Use the graph to calculate the acceleration of the object at 6 seconds.

 Acc = -5 m/s²

Use the graph to calculate the displacement of the car during the first 8 seconds.

D = 150 m

A 4-kg object is moving rightward with a velocity of +10.0 m/s and a leftward acceleration of -1.5 m/s^2. Draw a free body diagram of this situation.

N = 39.24 N

                      Fric = -6 N

                 u = .16                       W = -39.24 N

Ima Hurryin approaches a stoplight in her 1200-KG car that is moving with a velocity of +30.0 m/s. The light turns yellow; Ima applies the brakes and skids to a stop. If Ima's acceleration is –8.00 m/s².  Draw an FBD for the following situation and assume her tires are rubber and she is on dry asphalt.  Determine the displacement of the car during the skidding process.

Displacement = 56.25 meters

Newton's Third Law "For every action, there is an equal and opposite reaction."

Forces come in pairs, equal in magnitude and opposite in direction.

Force on bug from bus +100 N

Force on bus from bug -100 N

While driving, Anna Litical observed a bug striking the windshield of her car. Obviously, a case of Newton's third law of motion. The bug hit the windshield and the windshield hit the bug. Which of the two forces is greater: the force on the bug or the force on the windshield?

The forces are the same.  Forces come in pairs equal in magnitude opposite in direction.  The bug is effected more because it bug has less mass = less inertia = less ability to resist change in motion from the unbalanced force so the bug has a large acceleration.  Death!

Write an Expression for the X Component of the Final Displacement in Terms of the Given Quantities

Source: https://www.saratogaschools.org/webpages/tsanders/first_q_review.cfm?subpage=1387348

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