Energy, Machines & Motion

Lesson 2-5

Lesson 2 & 3: Notes

Energy: the ability of someone or something to perform work

Battery: can be a wet or dry cell

Wet Cell battery: has liquid electrolyte

Dry Cell battery: paste electrolyte

Negative Electrode - Cathode

Positive Electrode- Anode

Electrical potential Energy: stored electrical energy in the positive and negative terminals

Lesson 2: Activity

Creating a Wet Cell Battery-

-Zinc and Copper were the electrodes and copper sulfates was the electrolyte

-Electrolyte: the liquid that you placed the copper and zinc strips into, called copper sulfate

-Sulfur – the black substance on the zinc electrode

Lesson 3:

*Energy can be stored in a battery.

*Energy can be transformed from one form to another.

*Different devices use energy at different rates.

*”D” cell batteries used (1.5 volts)

* A knife switch opens and closes a circuit

*When a battery is used to run an electric device, it is discharging and it serves as an energy source for the device. In this inquiry, current flowing in the circuit carries the energy to the bulb. As the current flows through the bulb, the chemical energy stored in the battery becomes light and heat energy in the bulb. When all the battery’s available chemical energy has been converted to other forms of energy, the battery is “dead”.

*Electrical Current in a battery is

*Electrical Current in your home is

Lesson 4 Notes

Energy Transformations:energy changes from 1 form to another form

Light Bulb:

*Chemical →→→→ Electrical →→→→ Light →→→→ Heat

(potential) (going to light) (given off)

(mixing in battery)

Motor:

*Chemical →→→→ Electrical →→→→ Mechanical →→→→ Heat

(potential) (going to motor) (given off)

(mixing in battery)

**Heat is the final form of all energy transformations (see the energy transformations above).

Lesson 5 Notes:

-Force: any push or pull, measured in Newtons(N or kg-m/s/s)

-Elastic Force: associated with rubber bands, springs or other materials that stretch easily when acted upon by a force.

-Precision: to find the precision of a graduated cylinder or spring scale:

  1. Find the difference between the two consecutive numbers on scale
  2. Count the number of spaces between these two numbers
  3. Divide the difference by the number of spaces

Spring Scale Precision

Brown / 0.2
Green / 0.1
White / 1
Blue / 0.05
Yellow/gold / 1

-Weight: the measure of force or pull of gravity acting upon an object. Weight changes, the force of gravity on the moon’s surface is not as strong as the force of gravity on the surface of the earth. You would weigh only 1/6 as much on the earth (you weigh 6 times more on Earth than on the moon). Can be measured in newtons or pounds.

-Mass: the amount of matter in a object (measured in grams or kilograms). Mass will always be the same as it moves from place to place (assuming no matter is added or removed from the object).

-Slug: the British unit for mass

Additional notes:

  • Newton’s 2nd Law of Motion is F = ma
  • Lumen measures brightness
  • Filament – wire inside light bulb that heats and glows
  • Volts – unit of electrical force
  • Alternate Energy – wind power, solar power, and hydro-electro power
  • µ = micro
  • centi – 10-2
  • kilo - 103
  • cc = cubic centimeters
  • 1 Kilogram = 2.2 pounds