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projectile

An object in the air that is only subject to the force of gravity and wind resistance after it leaves the ground.

trajectory

Path of a projectile

range

distance a projectile travels horizontally along the ground

height

displacement in the y-axis; dy

parabola

A U-shaped curve characteristic of the graphs of quadratic equations

acceleration

(physics) a rate of change of velocity

Velocity

a speed in a particular direction.

time

A measure of change between two events or moments.

v0

The initial velocity of a projectile at an angle (m/s)

θ

Angular Displacement (rads)

v0y

The initial velocity of a projectile in the y-direction (m/s)

vx

The velocity of a projectile in the x-direction (m/s)

vfy

The final velocity of a projectile in the y-direction (m/s)

dx

The displacement in the x-direction (m)

T

1/f

a

acceleration (m/s2)

components

parts of a vector, one is parallel to the x-axis and the other one is parallel to the y-axis

horizontal acceleration

Acceleration is zero in the horizontal direction.

dx = vxt

The one equation we can use in the horizontal direction.

vertical acceleration

Acceleration is -9.8 m/s2 in the vertical direction.

vertical direction equations

dy = v0yt + ½at2

viy = 0 m/s

3 assumptions about vertical component

Projectile Motion

2D Motion in which the object moves at a constant velocity in one direction and accelerates in another

period

What is T?

Frequency

#cycles/second

h= (.5)+(g)(t)^2

Horizontal Projectile Motion from a height

r= V cos(o)sin(0)/4.9

Angular Projectile Motion starting and ending from the same height

2(3.14)(r)/T

Circular motion with a known speed and radius

-m(4)(3.14)^2(r)/T^2 or

Circular motion with a known time and radius (FC)

Accelerating

Even at a constant speed, an object moving in a circle is _______.

Magnitude...

... of a vector is always a positive quantity

centripetal acceleration

a = centripetal acceleration

circumference

2pi x r

-v^2/r

Two Equations for AC

Centripetal Force

A force directed towards the center of a circle that causes an object to follow a circular path

Frequency (F)

If you are given revolution per second or minute

H2

H2= s^-1, Hertz

f

1/T

If given revolutions/minute

Divide by 60 to get revolutions per second, then take the reciprocal to get T in seconds.

Vy

SIN

Galilean Transformation Formula for Velocities

An object's velocity relative to the ground is the vector sum of it's velocity relative to a moving reference frame plus the reference frame's velocity relative to the ground.

Galilean Transformation Formula for Position

(This one doesn't get used very often. The velocity formula is much more useful.)

a component vector

The projection of a vector along the axes of a coordinate system is called

Perpendicular

A wave in which the vibration of the medium is _______ to the direction in which the wave travels is called a transverse wave.

90<A<180

A vector that has components that lie along the -xaxis and the +yaxis is oriented at angle A measured counterclockwise from the +xaxis. Which of the following ranges give the values of angle A?

By equals 0

If the x-component of B equals the magnitude of B, them

scalar

a physical quantity that has magnitude but no direction

II

In the figure above, which diagram represents the vector addition, C=A+B?

IV

In the figure above, which diagram represents vector subtraction, C=A-B?

Vectors

have a magnitude and a direction e.g. velocity, displacement

cos 0 (theta)

The x component of the vector equals the vector's magnitude multiplied by which trigonometric function?

4

How many displacement vectors shown in the figure above have horizontal components?

d1 and d3

Which displacement vectors shown in the figure above have vertical components that are equal?

-d5,x; -d5,y

A hiker undergoes a displacement of d5 as shown in the figure above. A single displacement that would return the hiker to his starting point would have which of the following sets of components?

a baseball being thrown

Which of the following is an example of projectile motion?

a parabola

what does the center of mass follow when in projectile motion

a stone thrown into a lake

Which of the following exhibits parabolic motion?

Which of the following does not exhibit parabolic motion?

a flat piece of paper released from a window

B

At what point of the ball's path shown in the figure above is the vertical component of the ball's velocity zero?

move west at a speed that is equal to the bus's speed

A passenger on a bus moving east sees a man standing on a curb. From the passenger's perspective, the man appears to

straight down

Piece of chalk is dropped by a teacher walking at a speed of 1.5 m/s. From the teacher's perspective, the chalk appears to fall

scalar, scalar, vector

Identify the following quantities as scalar or vector: the mass of an object, the number of leaves on a tree, wind velocity

-3Vstudent

A student walks from the door of the house to the end of the driveway and realizes that he missed the bus. The student runs back to the house, traveling three times as fast. W…

29cm

An ant on a picnic table travels 3.0 x 10^1 cm eastward, then 25 cm northward, and finally 15 cm westward. What is the magnitude of the ant's displacement relative to its original position?

divided by the cosine of 0 (theta)

In a coordinate system, the magnitude of the x component of a vector and theta, the angle between the vector and xaxis, are known. The magnitude of the vector equals the x component

248 units 53.9 north of west

Find the resultant of these two vectors: 2.00 x10 ^2 units due east and 4.00 x 10^2 units 30.0 degrees north of west

equal to the horizontal component of its initial velocity

In the figure at the right, the horizontal component of the ball's velocity at A is

9.2 m

A track star in the long jump goes into the jump at 12 m/s and launches herself at 20.0 degrees above the horizontal. What is the magnitude of her horizontal displacement?

one component is perpendicular to v; the other component equals -v.

A boat travels directly across a river that has a downstream current, v. What is true about the perpendicular components of the boat's velocity?

606.9 km/h

A jet moving at 5000 km/h due east is in a region where the wind is moving at 120 km/h in a direction 30.00 degrees north of east. What is the speed of the aircraft relative to the ground?

7.5 m/s

A duck flying south for the winter has a velocity of 10.0m/s. If the duck is flying against a gust of wind with a velocity of 2.5 m/s, what is the resultant velocity of the duck?

(1/2)Vcar

A car travels down a road at a certain velocity, Vcar. The driver slows down so that the car is traveling only half as fast as before. Which of the following is the correct expression for the resultant velocity?

vecotrs

Multiplying or dividing vectors by scalars results in

vector

a displacement distinguished by magnitude and direction but not by location.

Vplayer, -2Vplayer

A football player runs in one direction to catch a pass, then turns and runs twice as fast in the opposite direction toward the goal line. Which of the following is a correct expression…

x axis: horizontal along the ground y axis: up and down

Which of the following is the best coordinate system to analyze a painter climbing a ladder at an angle of 60 degrees to the ground?

sin 0 (theta)

In a coordinate system, the y component of the vector equals the vector's magnitude multiplied by which trigonometric function?

d

Displacement (variable)

C

Light travels as fast as it can possibly go in air. This speed is 300 million m/s, and is labeled _______.

frame of reference

assists one in physics in which one chooses a place (point) a measure it against changes in position.

faster and faster

Objects that are falling toward Earth in free fall move

positive x axis pointing east; positive y axis pointing north

Which of the following is the best coordinate system to use to analyze the motion of

a bullet being fired from a gun

Which of the following is an example of projectile motion

Which of the following exhibits parabolic motion?

a person driving into a pool from a diving board

13 blocks

A jogger runs 10.0 blocks due east, 5 blocks due south and another 2 blocks due east. find the magnitude

12 m

A cave explorer travels 3.0 m east then 2.5 north finally 15m west. find magnitude

43m

A quaterback takes the ball from the line of scrimmage and runs back for 10 m then sideways for 15 m how far is the football displaced?

south of east

vector A points north and vector B points east, then vector C points

vx= constant and ay= -9.81

The motion of a projectile in free fall is characterized by

have a horizontal component

For an object to be a projectile, it must be in free fall and its initial velocity must

I only

A baby drops a ball from her hand resting on the serving tray of her high char. She knocks another ball from the same tray. Which of the following statements are true?

The horizontal displacement of a projectile depends on the

vertical component and horizontal component of its initial velocity

at the highest point of its path

A volleyball player taps a volleyball well above the net. The ball's speed is at least

magnitude of the vector

In a diagram, the length of a vector arrow represents the

axis

straight line which rotation takes place

rotataion

spinning around an internal axis

earth rotates around axis every 24 hours

what is an example of a rotation

Revolution

1 cycle = 1 year, 365 days; earths orbit around sun

earth orbiting around sun

what is an example of a revolution

directly proportional

when quantities change in the same direction

rotational velocity

rotations per time, depends on how fast you change DEGREES or angles

Tangential velocity

A velocity parallel to the Earth's surface

remains constant, increases

how does your rotational and tangential speed change when you walk from the center of the merry go round to the outer edge

gets increased

how is your tangential velocity affected if you cover greater distance

centripetal (towards the center)

when you twirl a can at the end of a string in a circular path, what is the direction of the force that acts on the can

does an object undergoing uniform circular motion accelerate? why?

yes, it changes direction (it has same speed but constantly changing direction)

centripetal

center seeking

lack of a force, 1st law (inertia)

if a string that holds a whirling can in its circular path breaks, what causes the can to movie in a straight line path, centripetal force, centrifugal force, or lack of a force? whic…

why is a centrifugal force called a fictitious force?

it does not result from a push or pull, it is an effect of rotation and inertia

increases (direct, quad)

a stopper is twirled in a horizontal circle. If you vary the following quantities, how will the velocity change:

decreases (direct, quad)

a stopper is twirled in a horizontal circle. If you vary the following quantities, how will the velocity change:

decrease (inverse, square)

a stopper is twirled in a horizontal circle. If you vary the following quantities, how will the velocity change:

tension, friction, gravity

name 3 forces that can act as a centripetal force

increase lever arm

if the amount of torque required remained constant, what can you do to decrease the amount force required to rotate the object

increase angle (90 degrees), increase lever arm, increase force

what can you do to achieve max torque exerted on an object

length, acceleration due to gravity

what 2 factors affect the period of a pendulum

increase, decrease

what happens to velocity as a pendulum swings downwards towards equilibrium? upwards away from equilibrium?

stays the same

if you changed the mass of the pendulum bob, how would the period be affected

does not

rotation velocity _______ depend on where you stand because the angle will be the same

rotational speed

at the center, tangential speed = o m's but you do have _______

simple harmonic motion

motion that is repeated because displacement and restoring force are proportional

equilibrium

1)starting point of SHM, object is in _______, fnet equals zero

Period (T)

the time for an object to complete one revolution

amplitude

The maxiumum displacement

bob

the object attached to a length of a string or rod (L)

inertia

_______ is the property of an object that leads it to resist any change in motion

length (L) and acceleration due to gravity (g)

what does the period of the pendulum depend on

what are the 2 forces exerted on the block (mass on a spring)

gravity (down) upward force of tension (directly proportional to the amount the string is stretched)

weight

A force that comes from gravity pulling down on any object with mass

Increases

As temperature increases, the vapor pressure of a liquid _______.

Decreases

A freight car moves along a frictionless level railroad

increased

If the pressure of a gas is increased, what must have happened to the volume?

force

(interactions between two objects)

Torque

A "force" that causes rotation because it is exerted at a distance from the axis of rotation.

lever arm

distance from the axis of rotation

increase torque

what happens when you increase the lever arm

Small

A force with a big mass has a _______ acceleration

Large

An object with a _______ heat capacity can absorb a lot of heat without undergoing much of a change in temperature.

move (linearly)

if you have a net torque, it will cause an object to _______