Physics unit 2

Projectile motion

any object thrown, launched, impelled, or otherwise projected into the air (occurs when an object has vertical and horizontal motion)

Hotiontal and vertical motion components should be

seperate

no other force except for ___ is on vertical motion

gravity

what projectile motion is

• all free fall

• thrown, batted, or kicked

• a cannon shot

what projectile motion is not

anything with an engine

any examples with air resistance

horizonatal projectile motion

rolling a marble off of a table,When an object is project straight out

In pies what graph must you use to differentiate between the horz and vert components

x | y

____|_____

|

|

when a ball falls or shoots out what’s the vert and horizontal motion

constant

problem solving components

• use little exponents to differentiate between x and y

• x and y are seperate

• time is used for both

constants for y

a = -9.8

Vo = 0 m/s

constants for x

a = 0 m/s

what do you need in the horz and vert graph to solve the problem

3 knowns 1 unknown

Vector

requires magnitude and direction

two numbers to fully describe them

Magnitude

the amount

Direction

which way

typically at an angle

Example is

velocity

———>

Tail to head shows magnitdue while where it’s pointed shows direction

10 m/s and 30 degrees, what do each tell you about the arrow

10 m/s is the amount and 30 degrees is the direction

Resultant vector

the sum of several vectors

equilibriatn vectors

equal in magnitude and opposite in direction to the resultant vector (counter it)

Breaking down vectors at an angle

^ ^
| /
| /

/
|____________>

Vy = vertical component (up or down)

Vx = horizontal component (left to right)

Add vectors

from tail to head place them next to each other and then draw a line that is the sum of both

Different directions

head to tail except the second one is underneath, the resultant is what is left over

Angled vectors

/\ is from the tail of the first vector to the head of the last vector (usually a straight line between the two )

_

When launching at an angle, velocity is still

a vector, you must break it into vert and horiz components

When breaking the velocity of a vector you use what

trig

symmetry

moriton is symmetrical as long as projectile begins and ends at the same height

displacement Horizontally

equal to the first half and the second half (multiply by 2 to get the total displacement)

Displacment vertically

total displacement is zero

velocity horizontally

constant

velocity vertically

Voy = -Vy (initial velocity is equal to negative velocity)

Acceleration horizontally

none

acceleration vertically

-9.8 m/s2

Time (angeled vectors)

time in the first segment is equal to time in the second