Download - Teaching Physics to Non- Physicists CRLA Conference 2012 (Session 69)

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Teaching Physics to Non-Physicists CRLA Conference 2012 (Session 69)

E=MC 2?

Presenters: William Wolfs, Mentor Tutor

Chyna Miller, Tutoring CoordinatorUniversity of Nevada Las Vegas, Academic Success Center

Outside

Inside

Any Questions?

It's 340 meters per second,

Einstein!

An F-18 fighter jet breaks the sound

barrier

STEM Degrees, 2007

Source: NSF

EngineeringAgricultural sciencesBiological sciencesEarth, atmospheric, and ocean sciencesChemistryMathematics/statisticsAstronomyPhysics

A12%

A-7%B+

3%

B+13%

B-6%

C+4%

C20%

C-6%

D4%

F or W23%

Grades for Biology Students

Physics:The Least You Need To Know

E=MC 2?

1. ΣF = ma2. x = ½at2 + v

0t + x

0

3. v = at + v0

4. v2 = v0

2 + 2ax5. f = μN6. a

c = v2/r

7. p = mv8. W = Fx = ΔE9. F

G = GMm/r2

10. FS = -kx

1. When something gets pushed on, its velocity changes.2. The path of an object over time depends on its initial velocity and acceleration.3. The velocity of an object over time depends on its initial velocity and its acceleration.4. The velocity of an object after a distance depends on its initial velocity and its acceleration5. The more of an object's weight a surface supports, the more friction between the object and surface.6. If an object moves in a circle, it is always getting pulled toward the center of that circle.7. The heavier something is and the faster its going, the more momentum it has.8. If an object feels a net push over a distance, its energy changes.9. Gravity between two objects depends on their mass and the distance between them.10. Pull on a spring and it pulls back.

1. ΣF = ma

What's wrong with Sisyphus?

Isn't he pushing ?

But the rock isn't moving!

Force Diagram

1. ΣF = ma 5. f = μN

A

B

C

A: Sisyphus' burly arms.

B: Boulder's immense weight

C. Friction with the bumpy ground

D. Normal Force

NO NET PUSH!Boulder wins again, Sisyphus

D

2. x = ½at2 + v0t + x

0 3. v = at + v

0 4. v2 = v

02 + 2ax

Where Does the Ball Go?

X

Why I Am Not A Golfer

2. x = ½at2 + v0t + x

0 3. v = at + v

0 4. v2 = v

02 + 2ax

That tree moved!You all saw it!

If A Real Golfer Hit A Golf Ball

2. x = ½at2 + v0t + x

0 3. v = at + v

0 4. v2 = v

02 + 2ax

A

B

B

C

A: Rising Velocity B: Constant Horizontal Velocity C: Falling Velocity

6. ac = v2/r

9. FG = GMm/r2

7. p = mv

Big Goat:300 lbs,10mph

Medium Goat:200 lbs15 mph

Little Goat:100 lbs30 mph

The Mystery of Math

You may not realize . . . .

If x=y and p=q:

x(p) = y(q)x+p = y+qx/p = y/q10x = 10y

A

B

C

θ

1. A2 + B2 = C2

2. Sinθ =A/C - A = (C)Sinθ3. Cosθ = B/C B = (C)Cosθ4. Tanθ = A/B

If ax2 + bx + c = 0, then:

Gravity on the Moon?

The Earth is about 100 times more massive than the moon.It is also about 4 times larger in radius.

Neil Armstrong prepares to jump 7 feet straight up

One Method to Rule Them All ......

1. Draw a picture.2. Label everything.3. Pick coordinates.4. Pick your physics.5. Do the math.

That doesn’t seem so hard. Or evil.

Draw a Picture!

A

B

C

Label Everything! A: Sisyphus' burly arms.

B: Boulder's immense weight

C. Friction with the bumpy ground

D. Normal Force

D

A

B

C

X YPick Your Coordinates!

θ

B

Bx

Byθ

Bx = Bsin(θ)By = Bcos(θ)

D

1. ΣF = ma2. x = ½at2 + v

0t + x

0

3. v = at + v0

4. v2 = v0

2 + 2ax5. f = μN6. a

c = v2/r

7. p = mv8. W = Fx = ΔE9. F

G = GMm/r2

10. FS = -kx

We have a situation where we are worried about how hard something is being pushed, so we pick the law having to do with force!

Pick Your Physics!

Do the Math!

Don’t be afraid. Those symbols don’t bite … well, they don’t eat much when they do.

To Sum Up:

1. Emphasize the simplicity and sparsity of the physical and mathematical tools needed.2. Emphasize the importance of intuition and creativity.3. Emphasize the wide applicability of the five-step method.

Thank you for joining us!

William Wolfs, Mentor TutorUNLV Academic Success [email protected]

Chyna Miller, Tutoring Coordinator UNLV Academic Success Center

[email protected]