Ch 1
What is the difference between an independent variable, a dependent variable, and a control?
independent variable: adjusted by experimenter
dependent variable: result that depends on independent variable
control: standard for comparison, does not get adjusted
give an example of a chemical change
fire burning
spoiled milk
cooking
using batteries
dying your hair
What is instantaneous speed? Give an example.
Speed at any given time; speed of a car at the state line
What is the difference between kinetic and potential energy?
kinetic: energy in the form of motion
potential: energy that is stored
How do atoms become charged?
by gaining or losing electrons
what is the unit and symbol for mass?
gram
"g"
what are some examples of constraints or limitations to technological design?
safety, cost, ease of use, natural laws, materials used
Positive acceleration is when an object's acceleration is increasing, like a plane taking off. Negative acceleration is when an object's acceleration is decreasing, like a car stopping at a stop sign.
what is the formula for work?
work = force x distance
voltage = current multiplied by resistance
compare line graphs, bar graphs, and circle graphs (pie charts)
line graphs: show changes over time
bar graphs: show quantities
circle graphs: show percents
how are science and technology related?
Science is asking questions to gain knowledge. Technology is the application of science to solve problems.
Describe the difference between distance and displacement.
Distance is how far something has moved. Displacement is how far and in what direction an object moved.
Give an example of a compound machine.
Scissors
Bicycle
Wheelbarrow
In a series circuit, the energy flows along one path.
In a parallel circuit, the circuit branches off and energy follows multiple paths.
compare and contrast scientific theory and scientific law
scientific theory: most logical explanation
scientific law: a rule based on observations
describe the two branches of physical science
chemistry: study of matter and energy at the molecular scale
physics: study of matter and energy at all scales
How do you calculate average speed?
total distance divided by total time
The calories from your breakfast being transformed from chemical to mechanical energy.
The radiant energy from the sun being transformed into electrical energy in a solar panel.
Electrical energy being transformed into light and thermal energy in a light bulb.
What is the difference between a conductor and an insulator? Name an example of each.
A conductor is a material in which electrons move easily, like a metal. An insulator is a material in which electrons are not able to move easily, like dry wood, rubber, or plastic.
what are the 7 steps of the scientific method?
ask a question
research
form hypothesis
design experiment
gather and analyze data
conclusion
share results
what are the 8 steps of the technological design process?
identify the problem
research the problem
generate possible solutions
select the best solution
create a model of the solution
test the model
refine and retest the model
communicate the results
How long will it take a train to travel 600 kilometers if it moves at a speed of 120 km/hr?
5 hours
Describe two kinds of inclined planes and provide an example of each.
The screw is an inclined plane wrapped in a spiral around a cylindrical post, like a lid to a jar. A wedge has one or two sloping sides, like an ax or a knife.
How can the strength of a magnetic field be increased?
by adding more turns to a wire coil called a solenoid, or by increasing the current passing through the wire