Section+5

=__//**Section 5- The Range of Projectiles: The Shot Put**//__=

toc

What Do You See?
12/13/10 page 184

The home score is y1 and x2 and the visitors is y2 and .1x2. They are parabolas. The projectiles are parabolas. The girl does a bicycle kick and a kid in back of her heads in it.

What Do You Think?
12/13/10 page 184

The lower the angle the farther it will go and the higher the angle the closer and higher up it will go. The more launch speed the the higher and farther it will go.

Acceleration Due To Gravity
12/14/10

Speed 2.40894
 * Time (s) || Distance (m) ||  ||
 * Acceleration (m/s/s) ||
 * .00000000000000000000000000 || .0000000000000000000000000000 || 0 || na ||
 * .053508 || .0500000 || 0.9344 || 12.0442 ||
 * .089924 || .10000000 || 1.373 || 10.9077 ||
 * .119426 || .1500000 || 1.6948 || 10.5253 ||
 * .144898 || .2000000 || 1.9629 || 10.3156 ||
 * .167650 || .2500000 || 2.1976 || 10.1821 ||
 * .188406 || .300000 ||  ||

V avg= distance/time V avg= (d2-d1/t2-t1) a=v2-v1/t2-t1
 * 10.1813 ||
 * .207604 || .3500000 || 2.6044 ||  ||

Physics Plus
12/14/10 page 188

There are mathematical and physical models. They are all parabolas. You can notice that with trajectories of different angles but initial speed are all: parabolas 45 is the longest range The pairs of angles are identical the smaller the angle the less time in the air

Checking Up
12/14/10 page 189

1. Constant speed and downward acceleration (-9.8) 2. The model must match reality in nature. 3. The height always gets higher but the range goes up until after 45 where it gets lower.

Physics Plus
12/16/10 page 190

A ball rolls off a table and lands on the floor

1

Description of Motion In the Vertical Direction
As soon as the ball leaves the table it begins to fall downward a distance of "y". As it falls it begins with a velocity of V(y)i=0 and accelerates at 9.8 m/s/s. This means it speeds up as if falls. The time it takes to reach the floor is t.

Vertical Variables
y V(y)i a=gravity T V(y)f

Vertical Equations
y=1/2GT^2 + V(y)iT g=V(y)f-V(y)i/T y=1/2(V(y)i+V(y)f)T Vyf^2=V(y)i^2+2GY

v=d/t doesnt work because there is a change in speed

Description of Motion In the Horizontal Direction
The ball moves at a constant speed as it moves a distance "x". It moves horizontally a time of "t' (same as in the vertical direction).

Horizontal Variables
X T Vx

Ty=Tx
 * Variable || x || y ||
 * d ||  || -75 cm= -.75 m ||
 * t ||  ||   ||
 * Vi || 5 m/s || 0 ||
 * Vf || 5 m/s ||  ||
 * a || 0 || 9.8 m/s/s ||

1) calculate Ty Y= 1/2gTy^2+V(y)iT

-.75=1/2(-9.8)T^2+0 T= .39s dx= VT dx= 5*.39 dx= 1.95m

a=Vf-Vi/t a= -3.822

Vf= 6.28

Physics To Go
12/17/10 page 194

1. 45 because it is in the middle of all of the angles 2a. higher and shorter distance b. lower and farther distance 3a. 60 b. 75 4. because thats a hard angle to get and they are running before it 5. He had a good initial speed 6a. downward b. east 7a. -29.4 m/s b. 5m/s c. 15 m 8. 45 9. 45 10a. downward b. 20.4s c. 408 m