Loading...

PPT – Chapter 2: Kinematics in One Dimension PowerPoint presentation | free to download - id: 6b953d-MjQ5N

The Adobe Flash plugin is needed to view this content

(No Transcript)

Ocean Science!

- Monday
- Review 20-2 reading guide questions.
- Review for tomorrows quiz
- Start frozen seas video
- Tuesday
- 20-2 Ocean Life Quiz
- Wednesday
- Research questions
- Finish Frozen seas video
- Thursday
- Ocean resources
- Friday
- Ocean Resources

Improvements

- Needs reordered according to gravity notes for

real. - Yes, definitely needs reordered
- Look up common misconceptions address them
- Use physics website more!
- More on weightstudents never get how to

calculate weight! Is important later too. - Weight on other planets!
- Make peanut butter jars with different weights

for different gravity! - Itd be coolest if it were a regular weight on

Earth!

Bonus!

- The acceleration due to gravity on the surface

of Jupiter is 25.9 m/s2. How many pounds would a

80.0 kg person weigh there? - (1.00 lb 4.46 N)

Bell Work 4/8/13

- New Bell Work Sheet!
- How many Newtons would a 885.0 kg object weigh on

Earths surface? (Use F ma, a 9.81 m/s2) - Convert this to lbs.

Bell Work 4/22

- A 45.0 kg ball experiences a force of 441.45 N.

What will its acceleration be? - A 90.0 kg ball experiences a force of 882.9 N.

What will its acceleration be? - W5SAYWoS

Schedule

- Wednesday
- Update grades
- See quizzes?
- Review labs
- Law of gravity notes!
- Thursday
- Law of gravity notes!

- Turn in your newtons laws demos lab!
- Make sure your grade sheet update! Show me for

some pts!!! 10 pts!!!!!

- Today you are going to
- take notes on gravity!
- So you can
- explain what affects the force of gravity

predict the gravity between different objects - Youll know youve got it when you can
- Answer the questions at the end of slide show

The 4 Fundamental Forces

Gravity!

- What does it do?
- Holds objects on Earth
- Makes objects fall
- Keeps satellites in orbit!

(No Transcript)

Gravity!

- Gravity is the attraction between any two objects

that have mass. - Its actually the weakest force!
- Its magic!!
- We dont really understand it (but then, thats

true of most fundamental stuff) - Sir Issac Newton wrote the law of universal

gravitation.

(No Transcript)

Gravity Mass

- Universal gravitation equation ?
- G 6.67 x 10-11
- 2 things affect the force of gravity ___________

and _____________ - The force of gravity is ___________________

related to mass.

Gravity Mass

- Gravity is the attraction between any two objects

that have mass. Why dont we notice the force of

gravity between all objects?

6.67 x 10-11 (50 kg)(5.97 x 1024 kg)

(6,371,000 m)2

491 N 110 lbs

6.67 x 10-11 (50 kg)(1.0 kg) (1 m)2

3.35 x 10-9 N 0.000 000 003 35 N 0.000 000 000

754 lb

- Gravity is the attraction between any two objects

that have mass. Why dont we notice the force of

gravity between all objects?

Even though the force of gravity between less

massive objects is, it would be noticeable if it

were the only force around. However, on Earth

the gravity of Earth overpowers these other

gravities, not to mention the fact that the

gravity between you other objects are pulling

in all sorts of directions, so they cancel out.

Far away from planets, the gravity of semi

large objects would have an effect. Its one way

we could deflect an oncoming asteroid!

Gravity Distance

- Universal gravitation equation ?
- G 6.67 x 10-11
- The force of gravity is ___________________

related to distance.

Gravity Distance

- The force of magnetism
- Which is stronger, gravity or magnetism?
- How are gravity and magnetism similar?
- How are gravity and magnetism different?

Gravity, Mass, Distance

- What happens to the force of gravity if
- mass doubles?
- distance doubles?
- So gravity depends more on ___.

Whats this table tell you?

- Would your mass or weight be any different on the

moon? Why? - Would your mass or weight be any different on the

top of a tall mountain? Why?

- What is the weakest fundamental force?
- Who discovered the law of gravity?
- What 2 things does the force of gravity depend

on? - Which does it depend on more?
- The force of gravity is directly related to ___,

and you can tell because ____ - The force of gravity is directly related to ___,

and you can tell because ____ - You would weigh ___ on the moon because _____.
- You would weigh ___ on Mt. Everest because

_____.

- Today you are going to
- take notes on weight freefall
- So you can
- calculate weight
- explain how objects freefall
- explain the behavior of projectiles
- Youll know youve got it when you can
- Answer the questions at the end

- Bell Work 5/5/14
- Do 1-7 on the Gravity and Projectile Motion Study

Guide 1 - Free Fallin Tom Petty https//www.youtube.com/wat

ch?vjVa0sISCjXc

Freefall!

- Freefall - when gravity is the only force acting

on an object. - All things on Earths surface fall with same

acceleration (_______). - If 2 objects were both dropped from the same

height, they would hit the ground at the same

time. Why dont we notice this? - Strobe light drops of water!

Air Resistance!

- Air resistance keeps all objects from falling

with the same acceleration on Earth. - Terminal velocity the fastest an object can

fall due to air resistance - Happens when force of air resistance weight
- FNET 0, therefore a _______!
- Moon Hammer Drop
- Feather in vacuum
- Elephant and feather on physics classroom

7 Minutes of Terror

- Landing
- 13,000 mph to 0 mph in 7 min
- https//www.youtube.com/watch?vKi_Af_o9Q9s
- What are some differences between Earth and Mars

that - affect how things
- fall there?

(No Transcript)

- Jill and Nick have a task. They both have to

push a cart down the hall with an acceleration of

5.0 m/s2. - Jills cart has a mass of 10.0 kg. How hard does

she have to push it? - Nicks cart has a mass of 20.0 kg. How hard does

she have to push it? - Even though Nick pushes his cart twice as hard,

his cart accelerates at the same rate because

Freefall!

- Why do all things fall with the same

acceleration? Shouldnt heavier objects fall

faster? - Earths force of gravity on an object is its

weight. - On the surface of Earth 1.0 kg weighs about 9.81

Newtons. - A 5.0 kg object weighs 44.05 Newtons. Calculate

its acceleration when dropped. - A 10.0 kg object weighs 98.1 Newtons. Calculate

its acceleration.

(No Transcript)

Why is the acceleration for everything the same?

- If something has twice the weight, it also has

twice the inertia, therefore its twice as hard

to accelerate. - Gravity is like horse drawn carriages, or a bunch

of tiny magnets! - Would two pieces of clay fall faster if combined?

Bell Work 4/25/13

- What 2 things determine the strength of the force

of gravity? - Do all objects fall with the same acceleration on

Earths surface? Why/Why not? - Do objects with twice the weight fall with the

same acceleration? Why/Why not? - Which falls faster, a bullet thats fired

horizontally or a bullet thats dropped? (or

neither)

Weight

Weight Weight dont tell me!

- Weight - force of gravity between an object a

planet. - FW ma (a is acceleration due to gravity)
- How much would a 1.00 kg object weigh on the

surface of Earth? In lbs?

- Today you are going totake notes on projectiles

and circular motion. - So you canpredict and explain the motion of

projectiles objects in circular motion - Youll know youve got it when you can
- Accurately answer the questions

Schedule

- Monday
- Gravity Notes Questions
- Tuesday
- Projectile Circular Motion Notes Questions
- Wednesday
- Orbits!
- Thursday
- Review Questions Begin Egg Drop Project
- Friday
- Build Egg Drop Project

7 Minutes of Terror

- Landing
- 13,000 mph to 0 mph in 7 min
- https//www.youtube.com/watch?vKi_Af_o9Q9s
- What are some differences between Earth and Mars

that - affect how things
- fall there?

Free Fall Reaction Time

- http//www.brianmac.co.uk/rulerdrop.htm

Projectile Motion

Projectile Motion

- Projectile motion motion in which an object

(projectile) is thrown near a planets surface,

and gravity is the only force acting on it - Ex. Thrown football, bullet shot, cow launched

from catapult. - Projectiles follow curved path called a parabola.

(No Transcript)

(No Transcript)

Projectile Motion

- Projectiles are in freefall!

Projectile Motion

- has horizontal (left right) vertical (up

down) motion. - The horizontal and vertical motion are

independent. - They dont affect each other!
- Which will hit the ground first, a bullet fired

from a gun or a bullet dropped from the same

height? - Mythbusters!!
- http//www.youtube.com/watch?vD9wQVIEdKh8

Horizontal Projectile Motion

- The horizontal (Vx) velocity of a projectile

doesnt change! - This makes sense because the net force in that

direction is ____________.

Vertical Projectile Motion

- A projectile
- takes as long to go up as it does to come down to

the same point at which you released it. - It will be going the same speed in the opposite

direction when it reaches its original height. - At its maximum height
- vy
- t

Projectile Motion

- What 2 things affect the distance of a

projectile? - What angle will launch a projectile farthest?
- What angles will launch projectiles the same

distance?

Bell Work 4/26/13

- What is the shape of a projectile?
- What angle will launch a projectile farthest?
- What angles will launch projectiles the same

distance? - List 3 things that affect the range (distance) of

a projectile.

Projectiles with Air Resistance

- The optimal angles to send balls flying the

farthest distances are around 40. For example,

for kicking or punting a football, you yield the

largest distance at a launch angle between 35

and 40. If you throw a small ball, such as one

used in track and field events or a baseball, the

ball is much smaller. Thus, the friction plays a

smaller role in the movement. Then the best angle

is almost 45.

Projectile Motion

Shoot a Monkey!

- http//www.youtube.com/watch?vcxvsHNRXLjw

Citing a rifle in

- Can an object be moving upwards if nothing is

pushing it? - Can an object be moving horizontally if nothing

is pushing it? - Is force required to keep an object in motion?

(Newtons ______ Law)

Bell Work

- Which direction do you think the doughnut will

travel when the string breaks?

Schedule

- Monday
- Check HW (Study guide), Review questions, Egg

Drop - Tuesday
- Notes on Circular Motion Orbits Egg Drop
- Wednesday
- Notes on Orbits Weightlessness Egg Drop
- Thursday
- Review Questions Finish Egg Drop Project
- Friday
- Test Egg Drop Project

- Today you are going totake notes on circular

motion. - So you canunderstand the direction of

acceleration velocity in circular motion and

centrifugal force. - Youll know youve got it when you can
- Accurately answer the circular motion questions.

Circular Motion

Circular Motion

- Objects in circular motion are accelerating

towards the center - Centripetal force force acting on an object in

circular motion pulls towards center of circle

Circular Motion

- Shape of horizontally thrown projectile

Centripetal Force

- Force diagram of object in circular motion

The forbidden F word!

- Centrifugal force imaginary center fleeing

force on an object in circular motion - NOT REAL
- Caused by inertiathe object wants to keep

traveling in a straight line

Car driving in circles

The forbidden F word!

- Circular motion demos
- Why does it stay there? (a law)
- What force acts on it? What direction?

Demos Puzzles

- What provides the force
- Toms puzzle
- Penny in balloon
- Marble tape
- Ball on string
- Color changing ball
- Ball on string through tube with weight

- Question A ball is being whirled around by a

string. If the string suddenly breaks (or is let

go), what direction will the ball travel A, B,

C, or D? (Neglect gravity) HAMMER THROW!!!

Doughnut on a string!

- http//www.youtube.com/watch?vTniQtoapVrQfeature

related

- Answer Path ___
- While attached to the string, the ball is forced

to follow a curved path. But once the string is

gone, no force is exerted and (law of inertia) it

follows a straight-line path.

Bell Work 5/1/13

- Answer questions 1-5 on the back of your Gravity

Projectile Motion Study Guide.

- Today you are going totake notes on orbits!
- So you canunderstand how satellites, moons, and

planets orbit things. - Youll know youve got it when you can
- Accurately answer the questions.

Projectile Motion Orbits

Projectile Motion Orbits

- Force diagram of object in circular motion
- (this should be earlier in slide show, when

circular motion first mentioned)

Projectile Motion Orbits

- Objects orbiting Earth are in free fall!
- Theyre falling!
- Gravity acts as the centripetal force
- Cannonball!

Satellites!

Earth Satellites

Earth satellite - projectile moving fast enough

to fall continually around Earth rather than into

it. The orbital speed for an object closely

orbiting Earth is about 8.0 km/s. That is 29,000

km/h (18,000 mi/h).

Earth Satellites

In the curvature of Earth, the surface drops a

vertical distance of nearly 5 meters for every

8000 meters tangent to its surface.

Earth Satellites

For a satellite close to Earth, the time for a

complete orbit around Earth, its period, is about

90 minutes.

Earth Satellites

A satellite must stay 150 kilometers (94 miles)

or more above Earths surface. Why cant we put

a satellite into orbit at low altitudes on Earth?

A satellite in circular orbit close to Earth

moves tangentially at 8 km/s (5 mi/s). During

each second, it falls 5 m.

Escape Velocity

To escape Earths gravity, an projectile must be

launched at a velocity of 11.186 km/s 25,000

mph. Rockets arent projectilesthey dont need

to go this fast. The firing of the rocket

provides a constant force. Pioneer 10, launched

from Earth in 1972, escaped from the solar system

in 1984 and is wandering in interstellar space.

Space Junk!

Bell Work 4/8/11 4 minutes

- Convert the following weight to Newtons.

A. 16 lb bowling ball

Find the mass of the

above in kilograms. - Explain how satellites orbit Earth.

Bell Work

- Get your notes study guide out finish the

last questions.

Schedule

- Monday
- Gravity Notes Questions
- Tuesday
- Circular motion! Build Egg Drop Project
- Wednesday
- Orbits! Build Egg Drop Project
- Thursday
- Review Questions Build Egg Drop Project
- Friday
- Review Build Egg Drop Project
- Monday
- Test!
- Tuesday
- Test Egg Drop Project

Weightlessness!

Weight Weightlessness

- How would it feel to be weightless?
- How do you feel your weight?

Weight Weightlessness

- What you feel as your weight is a sensation due

to the normal force - Just because you dont feel your weight, doesnt

mean youre weightless! - Astronauts in space are not really weightless.

Weight Weightlessness

- Astronauts are just in constant freefall! Nothing

is holding them up. They feel no normal force,

so they feel weighless. They float in the space

station because the space station is falling with

them. - Since theres nothing holding them up, they feel

weightless! - Drop Han Solo!

Weight Weightlessness

Would you like to be weightless?

Zero-G

(No Transcript)

- People On Vomit Comet
- http//www.youtube.com/watch?vN6ZJnIJRUCIfeature

related - Water balloons in zero gravity http//www.youtube.

com/watch?NR1featurefvwpvgTqLQO3L4Ko

end

Freefall on planets

- What all is the same on the surface of Earth?

Figure out that everything else must be equal to

acceleration due to gravity.

Egg Drop!

- You may purchase more materials during project.
- Materials list (5 pts)
- Include quantity, description, price, total

price, and net price. - Explain the purpose/advantage of each material
- Dont spend it all. You may purchase more

materials during project. - Blue print (10 pts)
- Anyone looking at the blueprint should be able to

build it - Everything must be to scale (1in 1 square)
- Explain how things are attached, lengths of

string - Newspaper
- Half Sheet 11.5 x 22.7 Full sheet 22.7 x 22.7
- Dont break your egg!
- If you do, you will have to clean it up.
- Make sure to calculate average speed show all

work. - Winners get a free homework pass!

Materials List

- Item Cost Total
- Full sheet of newspaper
- Straws
- 12 pieces of tape
- Net Cost

Egg Drop!

- Answer the following questions in complete

sentences on your graph paper. - Explain how your design relates to what you know

about air resistance and freefall. How is it

going to cause the egg to fall slowly? - If you had to name a possible problem with your

contraption, what would it be? (What might go

wrong?) - Hopefully your egg stopped accelerating pretty

soon after you let it go. What 2 forces were

equal at this point? - If there were 2 eggs in your basket, would it

have fallen faster? Why or why not? - Were there any problems with your project? How

could you improve upon it (even if there werent

problems)?

(No Transcript)

Bell Work 4/11/12

- What is a satellite?
- What are the forces acting on a satellite?
- How long does it take a satellite to orbit Earth?
- Can we see satellites with the naked eye?
- How fast do you have to throw a ball to throw it

off of the planet?

- Pluto has a mass of 1125 x 1022 kg and an

equatorial radius of 1195 km. (a) Calculate the

acceleration due to gravity on the surface of

Pluto. (b) A python weighs 980 N on Earth. How

much would it weigh on Pluto?

MP 1024 kg rP 1195 km 1195000 m 1.195 x

106 m G 6.67 x 10-11 N m2/kg2

g G MP/rP2 g (6.67 x 10-11)(1024)/(1.195 x

106 )2 g 4.78 x 10-20 m/s2

WE 980 N gE 9.8 m/s2 gP 0.59 m/s2 WP ? N

WE mgE 980 m(9.8) 100 kg m

W mg (100)(4.78 x 10-18m/s2) 4.78

x 10-18 N

- The elephant and the feather each have the same

force of gravity. - The elephant has more mass, yet both elephant and

feather experience the same force of gravity. - The elephant experiences a greater force of

gravity, yet both the elephant and the feather

have the same mass. - On earth, all objects (whether an elephant or a

feather) have the same force of gravity. - The elephant weighs more than the feather, yet

they each have the same mass. - The elephant clearly has more mass than the

feather, yet they each weigh the same. - The elephant clearly has more mass than the

feather, yet the amount of gravity (force) is the

same for each. - The elephant has the greatest acceleration, yet

the amount of gravity is the same for each.

Bell Work 4/8/11 5 minutes

- Convert the following weights to Newtons.

A. 16 lb bowling ball

B. 17 lb cat - C. 20,000 lb truck
- Find the mass of the above in kilograms.
- If an object has reached terminal velocity, what

is the net force on the object? Whats its

acceleration? - T/F An object in orbit is actually falling.

Bell Work 4/4/11 5 minutes

- START NEW MONDAY BELL RINGER FOR 4TH QUARTER ?
- Define mass according to chemistry and according

to physics. - W5SAYW

Bell Work 3/30/12 5 min

- Robbie can throw a 3.0 kg medicine ball with an

acceleration of 10.0 m/s2. What acceleration

could he give a 9.0 kg medicine ball? Show your

work! - If you were in a plane, would your weight or mass

change? Why?

- The moon has a radius of 1.74 million meters and

a mass of 7.32x1022 kg. In both MKS and FPS

units, determine the acceleration due to gravity

on the lunar surface.

M 7.32 x 1022 kg r 1,740,000 m 1.74 x 106

m a ?

a GM r2 a (6.67 x 10-11)(7.32 x

1022 kg ) (1.74 x 106)2

48.824 x 1011 3.02 x 1012

16.17 x 10-1

1.62 m/s2

Bell Work 4/11/11 5 minutes

- Mass (kg) Weight on Earth
- Newtons Pounds
- 1 kg ____N ____lbs
- 50 kg ____N ____lbs
- 0.102 kg ____N ____lbs
- _____ kg 500 N ____lbs
- _____ kg 50 N ____lbs
- _____ kg ____N 2,000 lbs
- W5SAYW

Bell Work 3/29/12 5 min

- A force of 250.0 lbs acts on an object with a

mass of 8.0 kg. Whats its acceleration? - What is gravity?

Bell Ringer 4/1/11 2 min

- If the mass of an object magically doubled, the

force of gravity between it and other objects

__________. - If the distance between two objects doubles, the

force of gravity between them is ____ what it

was.

Bell Work 4/7/11 5 minutes

- Use the conversions between lbs, kg, and N in

your notes to answer the following questions. - What is the difference between mass and weight?

Give 2 units that measure weight and 1 unit that

measures mass. - Change the following weights to Newtons.

12 lb bowling ball

117 lb teen

1600 lb car - Find the weight of the following masses in

Newtons AND pounds. - 1 kg 5 kg 1000 kg

- If Pandora has a mass of 5.00 x 1024 kg and a

radius of - 6.00 x 103 km, find the weight of a 110 kg Navi

on Pandoras surface. (Pay attention to the

units!)

MP 5.00 x 1024 kg mN 110 kg r 6.00 x 103

km 6.00 x 106 m W Fg ?

Fg GMPm r2 Fg (6.67 x

10-11)(5.00 x 1024 kg )(110 kg)

(6.00 x 106)2 Fg 1019 N

Tips for using the G equation.

- Make sure you square r!
- Youll be dealing with big numbersdont forget

the exponents! x 10-11! - Double check your answers.

Satellite Motion

- What is a satellite?
- What are the forces acting on a satellite?
- How long does it take a satellite to orbit Earth?
- Can we see them with the naked eye?
- How fast do you have to travel to get escape this

planet?

14.2 Circular Orbits

The speeds of the bowling ball and the satellite

are not affected by the force of gravity because

there is no horizontal component of gravitational

force.

14.2 Circular Orbits

- The satellite is always moving at a right angle

(perpendicular) to the force of gravity. - It doesnt move in the direction of gravity,

which would increase its speed. - It doesnt move in a direction against gravity,

which would decrease its speed. - No change in speed occursonly a change in

direction.

14.4 Energy Conservation and Satellite Motion

For a satellite in circular orbit, no force acts

along the direction of motion. The speed, and

thus the KE, cannot change. What force or forces

hold satellites in orbit?

14.2 Circular Orbits

A satellite in circular orbit close to Earth

moves tangentially at 8 km/s (5 mi/s). During

each second, it falls 5 m beneath each successive

8-km tangent. What happens to the velocity of a

satellite as the distance from Earth increases?