•Define and solve for Kinetic energy

Launch: What is the definition of physics? Physics is the study of matter and matter’s relationship with force and energy. Monday 5 January

Agenda

Launch/Kick Of

10 min

5%

Reading

20 mins

50%

Notes/Questions

20 mins

45%

Homework: Read and Take notes:

8.4-8.5

Logistics

If you want to go over your test come in at lunch.

Semester supplies

Get a spiral notebook/composition book for notes

A pack of index cards

Check for completion (with this week’s notes) by Friday

Tardys and not doing HW = lunch detention/parent phone call home

Failing a quiz = phone call home

3 failed quizzes = parent conference

This Matters

The Struggle Matters

I Matter

Be

Be

Be

Be

Respectful

Responsible

Honest

Accountable

Work, Power, and Energy

What is energy?

ENERGY is the ability to make things move or change

Measured in Joules (J)

Kinetic Energy

KINETIC ENERGY is the energy of motion

It is a SCALAR quantity – it does not have direction Depends on mass and speed

Kinetic Energy

Formula:

KE = ½mv

2

mass (in velocity (in kg) 1 Joule = kg m/s)

• m2/s2

Kinetic Energy

The bird has a mass of 2 kg. It is flying at a speed of 5 m/s. Find its

KE

= ? energy. kinetic m = 2 kg v = 5 m/s

KE = ½mv2

KE = ½(2 kg)(5 m/s)2

= 25 J

By the end of the day today, IWBAT…

•Define and solve for Potential energy

Launch: What is the kinetic energy of a

1 kg baseball traveling at a speed of

10 m/s?

Tuesday 6 January

Agenda

Launch/Kick Of

10 min

5%

Notes/Questions

30 min

45%

Practice

10 min

55%

Homework: Read and take notes: 8.6

Review

What is the unit for energy?

What are the two kinds of energy of motion? What does kinetic mean?

What does KE depend on?

KE ~ Square of the speed

The kinetic energy of an object is directly proportional to the square of its speed.

That means that for a twofold increase in speed, the kinetic energy will increase by a factor of four.

How would a threefold increase in speed afect the kinetic energy?

What would a graph of KE as a function of speed look like?

Potential Energy

An object with POTENTIAL ENERGY has the ability (or potential) to move or change

Sometimes called “energy of position” or

“stored energy”

There are 3 types of potential energy:

Gravitational Potential Energy

Elastic Potential Energy

Chemical Potential Energy

Gravitational Potential Energy

Potential Energy due to an object’s position Formula:

PE = mgh

height (in mass (in meters) kg) acceleration of gravity (9.8

2

Gravitational Potential Energy

If your egg drop device has a mass of 2 kg, how much potential energy does it hold at a height of 10 meters?

PE =

PE = ? mgh PE =

(2 kg)(9.8 m/s2)(10 m) = m = 2 kg

196 J g = 9.8 m/s2 h = 10 m

Gravitational Potential Energy

•The person has more potential energy at the top of the stairs than at the bottom.

Gravitational Potential Energy

Where does the egg have more potential energy? Why?

Elastic Potential Energy

Potential energy due compression or expansion of an elastic object

Chemical Potential Energy

Potential energy stored within the chemical bonds of an object

By the end of the day today, IWBAT…

•Introduce Conservation of Energy (COE) and use COE to solve for KE and PE

What is the total energy of a 5 kg toy car traveling 4 m/s on top of a table that is 1 m of the ground?

(use 10 m/s2 for g)

Wednesday 7 January

Agenda

Launch/Kick Of

10 min

5%

Review

10 min

15%

Quiz

20 min

70%

Notes

10 min

10%

Homework: Print out Lab

Review

What is the unit for energy?

What are the two kinds of energy of motion? What does kinetic mean?

What does KE depend on?

What does potential mean?

What does gravitational PE depend on?

Graphic Organizer Summary

Joules (J)

PE= mgh

Potenti

al

Gravitation

al

Elastic

Kinetic

Chemica

l mass KE = ½ mv2

mass

velocity position By the end of the