Science Daily

Do Now- 5/14List what equation you would use to calculate the answers to the following word problems.a. A car moves a 25 m/s for 8 seconds. What distance did the car move?b. You apply a force of 16 N to push a 4 gram pencil. What is the acceleration of the pencil and you push it?c. It takes 40,000 J of work to move a box 50 meters. How much force does moving the box require?

agendaDo now (2 minutes)Foldable notes (10 minutes)Group Practice (10 minutes)IP (15-20 min)Closing (5 minutes)Progress ReportsReminders Grades close for interims TOMORROW- any make-up work must be in my box by 3:45 p.m. to be counted. I will not take any work that was due before 5/4See me AFTER SCHOOL for questions about grades

Foldable You need two sheets of paper

Algebra OverviewDensity ExampleF=ma Example Velocity ExampleAlgebra OverviewRearranging equations: - You can do anything to an equation as long as you do the same to each side

- Anything divided by itself is 1Density EquationD = m/v

If the density of an object is 6 g/mL its volume is 3 mL, what is its mass?Solving for: m (mass)D = m vx V V x V x D = mVelocity equationV = d/t

An object moves for 35 seconds at a velocity of 10 m/sec. Far did it move?Solving for: d (distance)V = d tx t t x t x V = dF=ma equationF = ma

A force of 600 N is needed to accelerate a wagon 2 m/s2. What is the mass of the wagon? Solving for: m (mass)F = maaaF = ma V = d/t

An object moves for 40 meters at a velocity of 10 m/sec. How long did this take?Velocity equationSolving for: t (time)V = d tx t t x t x V = dVVt = d v Develop equations for the following word problems A train traveled with a velocity of 40 m/s for 20 seconds. How far did the train travel?

Gold has a density of 19.3 g/cm3. What is the volume of a sample of gold that has a mass of 30 g?

You do 39 J of work to lift a book a distance of 3 meters. How much force did you apply to the book?

Independent WorkComplete the practice sheet of word problems on your own.

Remember to:Only use the variables necessaryStep 1: Determine what you are solving for.Step 2: Determine what equation you need to use.Step 3: Rearrange the equation if necessary.Step 4: Solve problem 1. Identify Variables 2. Plug numbers into Equation 3. Solve & Include Units

CLOSING Show all your work1. Iron has a known density of 7.87 g/cm3. What would be the mass of a 1.2 cm3 piece of iron?2. What is the velocity of a jet plane that travels 732 meters in 8.2 seconds?

Do NowState whether you think each of the following require work and why.

a. You push a shopping cart through the grocery store.b. You try and push a box forward but it is very heavy and does not move.c. You think through a math problem. Do NowState whether you think each of the following require work and why.

You lift a coffee mug to take a drink.

b. You try to push open a door but it is locked shut and doesnt open.

c. You ride your bike up a hill in a dream. WorkWork is done only when a force cause a change in the position or the motion of an objectwork = force x distance or W = F x d

Workwork = force x distance or W = F x dThe SI unit for force is newton (N). The SI unit for distance is meter (m). The SI unit for work is joule (J).

1 J = 1N x 1mA fork lift moves 34m carrying a 1023N box across the warehouse floor. How much work is done by the fork lift. Step 1: Identify your variables:F = 1023 N W = ? d = 34 mStep 2: Plug numbers into correct equation W = F x dW = 1023 N x 34 mStep 3: Solve equation W = 1023 N x 34 m W = 34,782 J How much work is done by a person who uses a force of 27.5N to move a grocery buggy 12.3m?Step 1: Identify your variables:F = 27.5 N W = ? d = 12.3 mStep 2: Plug numbers into correct equation W = F x dW = 27.5 N x 12.3 mStep 3: Solve equation W = 27.5 N x 12.3 m W = 338.25 J Practice ProblemsYou use 4 N of Force to lift a coffee mug .25 meters. How much work have you done?

A man pushed a 5000 gram box 25 meters. This involved 150 N of force. How much work is done.

A woman pushes a box with 20 N of force but cannot move it. How much work has she done? PowerThe rate at which work is done (how much work is done in a given amount of time)

Example: What is more tiring?Walking up a flight of stairsor Running up a flight of stairs? Both require the same amount of Work but one you do faster (faster = more power)

PowerPower = Work orP = W time t

Power is measured in Watts: W = 1Joule/1 secondIt takes 100,000 J of work to lift an elevator 18 m. If this is done in 20 s, what is the average power of the elevator during the process? Step 1: Identify your variables:W = 100,000 J P = ? t = 20 sStep 2: Plug numbers into correct equation P = W/tP =100,000J/20sStep 3: Solve equation P= 5000 W (or 5 kW)While rowing across the lake during a race, John does 3960 J of work on the oars in 60 seconds. What is the power in Watts?Step 1: Identify your variables:W = 3960 J P = ? t = 60 sStep 2: Plug numbers into correct equation P = W/tP =3960J/60sStep 3: Solve equation P= 66 WExit TicketYou apply 20 N of force to lift a book a distance of 3 meters. How much work did you apply to the book.

2. If you did 48 J of work to lift a box in 4 seconds how much power did you have?

Exit TicketA force of 825 N is needed to push a car across a lot. Two student push the car 35 m . How much work is done?A power mower does 450,000 J of work in 1800 seconds. What power does it develop?

Do NowReview problem. Rearrange equations to solve for the following:

Mass (F=ma)b. distance (W=Fd)c. Work (P=W/t)d. time (P=W/t)

TYPES OF ENERGY

Mechanical, Electromagnetic, Electrical, Chemical, Sound and ThermalWhat is Mechanical Energy? Energy due to a objects motion (kinetic) or position (potential).

The bowling ball has mechanical energy.

When the ball strikes the pins, mechanical energy is transferred to the pins!

Examples of Mechanical Energy

What is ElectromagneticEnergy? Light energy

Includes energy from gamma rays, xrays, ultraviolet rays, visible light, infrared rays, microwave and radio bands

What is Electrical Energy? Energy caused by the movement of electrons

Easily transported through power lines and converted into other forms of energy

What is Chemical Energy? Energy that is available for release from chemical reactions.

The chemical bonds in a matchstick store energy that is transformed into thermal energy when the match is struck.

Examples of Chemical Energy

Sound EnergyEnergy transferred through a medium (ex: air, water)

The changes in pressure in the air caused by sound are picked up by sensitive bones in your ears your brain interprets these changes as sound

What is Thermal Energy? Heat energy

The heat energy of an object determines how active its atoms are.

A hot object is one whose atoms and molecules are excited and show rapid movement.

A cooler object's molecules and atoms will show less movement.

What is Nuclear Energy?Ex: Sun, Stars,Nuclear Power PlantEnergy stored in the nucleus of an atom from fission or fusionFission splitting an atomFusion fusing the nuclei of 2 atoms

QUIZ TIME!What type of energy cooks food in a microwave oven?ELECTROMAGNETIC ENERGYWhat type of energy is the spinning plate inside of a microwave oven?MECHANICAL ENERGY

QUIZ TIME!Electrical energy is transported to your house through power lines.

When you plug an electric fan to a power outlet, electrical energy is transform into what type of energy?

MECHANICAL ENERGY

QUIZ TIME!What energy transformation occurs when an electric lamp is turned on?

ELECTRICAL ENERGYELECTROMAGNETIC ENERGY

What type of Energy is shown below?NUCLEAR ENERGY

What types of energy are shown below?Mechanical and Thermal Energy(Dont forget friction)

What type of energy is shown below?Chemical Energy

What types of energy are shown below?Electrical, Mechanical andElectromagnetic Energy

What type of energy is shown below?Sound Energy

What type of energy is shown below?Chemical Energy (yummy)

What type of energy is shown below?Thermal Energy

Rube Goldberg MachinesUses the transfer of energy to perform a very simple task in a very complex manner

Honda Cog: Rube Goldberg Machine List the following energies in your notes:

MechanicalElectromagneticElectricalChemicalSoundThermalNuclear As you watch the video list as many examples as you can for each

(Hint: all are present except for two)Exit Ticket Movement of photons in a flashlight Energy stored in the bonds in foodStars use energy in the nucleus of atomsA rock is rollingVibrations through speakersElectrons traveling through a wireMolecules vibrate and heat up in an oven a. Thermalb. Electricityc. Chemicald. Sounde. Electromagneticf. Nuclearg. Mechanical

Draw a flow map showing the flow of energy transformations in a car from starting vehicle to driving. You should have 5 different types of energy.

Energy Transfer

ChemicalElectricalElectricalElectricalSoundLight(Electromagnetic)ThermalMechanical

Do NowWhen Ms. McClain drops her pen it originally has potential energy and it then changes into kinetic energy. What happens to the energy the pen has when it hits the floor? Conservation of EnergyLaw energy cannot be created or destroyed

PEPEKE

Potential EnergyKinetic EnergyMechanical EnergySound EnergyThermal Energy

PE = 0 kJKE = 1,920 kJTotal = 1,920 kJPE = 588 kJKE = 1332 kJTotal = 1,920 kJPE = 1,920 kJKE = 0 kJTotal = 1,920 kJ

Every time one type of energy is transformed into another you lose energy from the system.

The less energy you lose, the more efficient the system is.Is this energy destroyed when it is lost?

What happens to it?

NoIt escapes the system as another form of energy