What puts the thrill in a thrill

ride?Elizabeth Buckholtz Toledo Public Schools

• Show videos of Cedar Point roller coasters.

Elizabeth Buckholtz Toledo Public Schools

What puts the thrill in a thrill ride?

Elizabeth Buckholtz Toledo Public Schools

Kinetic Energy

• The energy of motion is called kinetic energy.• I think of kinetic energy as

the hurt factor.

Elizabeth Buckholtz Toledo Public Schools

Kinetic Energy

Elizabeth Buckholtz Toledo Public Schools

Kinetic Energy

Elizabeth Buckholtz Toledo Public Schools

Kinetic Energy

K.E. = mass x velocity2

2

Elizabeth Buckholtz Toledo Public Schools

Kinetic Energy

K.E. = mass x velocity2

2

20 grams 10 mi/h.02 kg 4.5 m/s20.25 m2/s2.4 kg m2/s2

.2 kg m2/s2.2 Joules

Elizabeth Buckholtz Toledo Public Schools

Kinetic Energy

K.E. = mass x velocity2

2

3.5 kg 4.5 m/s20.25 m2/s270.875 kg m2/s235.45 kg m2/s235.45 Joules

Elizabeth Buckholtz Toledo Public Schools

Kinetic Energy

• .2 Joules • 35.45 Joules

Elizabeth Buckholtz Toledo Public Schools

Kinetic Energy

•The greater the mass of a moving object, the more kinetic energy it has.

Elizabeth Buckholtz Toledo Public Schools

Kinetic Energy

Elizabeth Buckholtz Toledo Public Schools

Kinetic Energy

Elizabeth Buckholtz Toledo Public SchoolsAroldis Chapman

Kinetic Energy

K.E. = mass x velocity2

2

.15 kg 45 mi/h400 m2/s260 kg m2/s230 kg m2/s230 Joules

Elizabeth Buckholtz Toledo Public Schools

Kinetic Energy

K.E. = mass x velocity2

2

.15 kg 100 mi/h45 m/s2025 m2/s2304 kg m2/s2152 kg m2/s2152 Joules

Elizabeth Buckholtz Toledo Public Schools

Kinetic Energy

• 30 Joules • 152 Joules

Elizabeth Buckholtz Toledo Public Schools

Kinetic Energy

• The faster an object moves, the more kinetic energy it has.•Kinetic energy depends on

both mass and velocity.

Elizabeth Buckholtz Toledo Public Schools

Kinetic Energy

K.E. = mass x velocity2

2

Elizabeth Buckholtz Toledo Public Schools

Potential Energy

• Potential Energy is stored energy.– Stored chemically in fuel, the nucleus of atom, and

in foods.– Or stored because of the work done on it:• Stretching a rubber band.• Winding a watch.• Pulling back on a bow’s arrow.• Lifting a brick high in the air.

Elizabeth Buckholtz Toledo Public Schools

Gravitational Potential Energy

• Potential energy that is dependent on height is called gravitational potential energy.

Elizabeth Buckholtz Toledo Public Schools

Gravitational Potential Energy

• The formula to find G.P.E. isG.P.E. = Mass X Height x Gravity.

Elizabeth Buckholtz Toledo Public Schools

9.8m/s2

Gravitational Potential Energy

a marble on your desk

G.P.E. = Mass X Height X 9.8 m/s2.02 kg 1 m

.2 JoulesElizabeth Buckholtz Toledo Public Schools

Gravitational Potential Energy

a marble on the Empire State Building

G.P.E. = Mass X Height X 9.8 m/s2.02 kg 443 m

87 JoulesElizabeth Buckholtz Toledo Public Schools

Gravitational Potential Energy

• .2 Joules • 87 Joules

Elizabeth Buckholtz Toledo Public Schools

Gravitational Potential Energy

•The higher an object is, the more gravitational potential energy it has.

Elizabeth Buckholtz Toledo Public Schools

Gravitational Potential Energy

A bowling ball on the Empire State Building

G.P.E. = Weight X Height X 9.8 m/s23.5 kg 443 m

15,000 JoulesElizabeth Buckholtz Toledo Public Schools

Gravitational Potential Energy

• 87 Joules • 15,000 Joules

Elizabeth Buckholtz Toledo Public Schools

Gravitational Potential Energy

•The more an object weighs, the more gravitational potential energy it has.

Elizabeth Buckholtz Toledo Public Schools

Gravitational Potential Energy

•“The bigger they are the harder they fall” is not just a saying. It’s true. Objects with more mass have greater G.P.E.

Elizabeth Buckholtz Toledo Public Schools

Energy Transformations

•Most forms of energy can be transformed into other forms.• One of the most common

transformations is between potential and kinetic energy.

Elizabeth Buckholtz Toledo Public Schools

Energy transformations (falling objects)

maximum heightmaximum GPE

heightdecreasing

velocity increasing

Height 0 meters

GPEdecreasing

KEincreasing

GPE0 Joules

has a little KE

maxium velocitymaximumKEElizabeth Buckholtz Toledo Public Schools

Energy transformations (falling objects)

• Where did all that KE come from?• As the water fell,

PE was converted to KE.

Elizabeth Buckholtz Toledo Public Schools

Energy Transformation(object thrown upward)

height increasingPE increasing

maximum heightmaximum PE

very littleheightvery little PE

Velocity isdecreasingKE decreasing

balanced forceball does not movenoKE

velocityincreasingKEincreasing

maxvelocitymaxKEElizabeth Buckholtz Toledo Public Schools

Energy Transformation(object thrown upward)

• As objects fall potential energy is transformed to kinetic energy.

• An object has maximum potential energy at the top of it’s path.

• As an object falls potential energy is transformed into kinetic energy.

• A moving object has maximum kinetic energy at the lowest point of it’s path.

Elizabeth Buckholtz Toledo Public Schools

Conservation of Energy

•Energy can not be created or destroyed, it changes forms.

Elizabeth Buckholtz Toledo Public Schools

Kinetic-Potential Energy Conversion

Roller coasters work because of the energy that is built into the system. Initially, the cars are pulled mechanically up the tallest hill, giving them a great deal of potential energy. From that point, the conversion between potential and kinetic energy powers the cars throughout the entire ride.

Elizabeth Buckholtz Toledo Public Schools

• Show videos of student roller coasters

Elizabeth Buckholtz Toledo Public Schools

Roller Coaster Challenge

• You are going to be working in teams to build a roller coaster– 12 feet of pipe insulation– 1 marble– Tape

• Requirements– Two hills– 1 trick (corkscrew, loop, twist, etc)

Elizabeth Buckholtz Toledo Public Schools

Roller Coaster Challenge

• Get into your groups.• Plan your roller coaster.• Draw a diagram.• Diagram must include– Name of roller coaster– Place of maximum gravitational potential energy– Place of GPE transforming into kinetic energy– Place of maximum KE (assuming ideal conditions)

Elizabeth Buckholtz Toledo Public Schools

Example Diagram

Elizabeth Buckholtz Toledo Public Schools

Roller Coaster Challenge

• Present designs

Elizabeth Buckholtz Toledo Public Schools

Build Roller Coasters

• minimum three days• students keep a journal–At the end of every day they record •problems encountered & solutions•design changes and why•Observations

Elizabeth Buckholtz Toledo Public Schools

Sample Journal Entry

Elizabeth Buckholtz Toledo Public Schools

Roller Coaster Derby Day• Each group presents their roller coaster.• Tell the name• Tell the features, including measurements• Points out point of – Highest GPE– Highest KE– Place where GPE is transforming to KE

• Answer questions• Run coaster• Videotape if possible.

Elizabeth Buckholtz Toledo Public Schools

Sample Roller Coaster

Elizabeth Buckholtz Toledo Public Schools

Roller Coaster Derby Day

• Use graph paper to draw a scale diagram of their final roller coaster.

• Label points of – Greatest GPE– Greatest KE– Transformations between GPE and KE

Elizabeth Buckholtz Toledo Public Schools

Sample Graph

Elizabeth Buckholtz Toledo Public Schools

Assessment

• Use rubrics.• Original design• Journal• Team work and productivity (can be self and

peer assessed)• Final roller coaster• Diagram

Elizabeth Buckholtz Toledo Public Schools

Assessment

• Class choice – which roller coaster they would most want to ride.

• Longest drop• Highest hill• most tricks

Elizabeth Buckholtz Toledo Public Schools

Other topics

• Accelerations– Positive– Negative– Centripetal

• Average speed• Distance• Displacement• Newton's laws of motion

Elizabeth Buckholtz Toledo Public Schools

Version 2 updated 8/9/12 (fixed spacing, labeling and 1 decimal error)

Elizabeth Buckholtz Toledo Public Schools

references

• http://www.google.com/search?aq=f&sourceid=chrome&ie=UTF-8&q=effect+of+mass+on+kinetic+energy#sclient=psy&hl=en&source=hp&q=powerpoints+potential+kinetic+energy&pbx=1&oq=power+points+potential&aq=1jl&aqi=g-jl2&aql=&gs_sm=c&gs_upl=17026l23405l0l26142l22l20l0l1l1l0l347l3629l0.12.5.2l19&bav=on.2,or.r_gc.r_pw.&fp=4314f23e9084643a&biw=1366&bih=600

Elizabeth Buckholtz Toledo Public Schools