Scientific Method & Engineering Design
In an experiment, which variable is deliberately changed by the scientist?
The independent variable.
A push or pull acting on an object is called what?
A force.
What does the law of conservation of energy state?
Energy changes form but is not created or destroyed.
How do mechanical waves transfer energy?
By vibrating particles in a medium.
Which variable belongs on the x-axis when graphing distance versus time?
timer
Why is a control group essential in experimental design?
It provides a baseline for comparison.
What happens when two equal forces act in opposite directions on an object?
The object remains at rest or moves at constant velocity (balanced forces).
What happens to gas particles when thermal energy is added?
They move faster and spread farther apart.
How can you identify a transverse wave?
Particles vibrate perpendicular to the direction the wave travels.
Why is a line graph best for showing changes over time?
shows trends and continuous change.
Which calculation determines average speed?
Distance divided by time.
A heavier cart needs more force to get the same acceleration as a lighter cart. Which law does this support?
Newton’s Second Law.
Why does pressure increase in a heated, sealed container?
Particles collide more frequently and with greater force.
What type of wave is sound?
A mechanical longitudinal wave.
Why does friction often reduce motion energy?
It converts kinetic energy into thermal energy.
Two groups get different results when testing insulation materials. What is the most scientific next step?
Compare procedures to identify possible sources of error.
Why does a soccer ball accelerate when it is kicked but a book on a desk does not?
The kick creates unbalanced forces, while the book experiences balanced forces.
Why does thermal energy always flow from hot objects to cold objects?
Energy naturally moves toward equilibrium.
Why does constructive interference increase wave amplitude?
Wave displacements add together.
How does the particle model of matter explain changes in pressure and temperature?
As particles move faster, collisions increase, raising temperature and pressure.
Why is repeated data showing a clear pattern stronger evidence than a single observation?
Repeated data increases reliability and reduces the impact of random error.
How does Newton’s Third Law apply to designing car bumpers?
During collisions, forces act in equal and opposite pairs, so bumpers are designed to manage those forces safely.
How does regenerative braking demonstrate energy transformation and efficiency?
t converts kinetic energy into electrical energy instead of losing it as heat.
Why do electromagnetic waves with shorter wavelengths carry more energy?
They have higher frequency.
Why is physics best described as the study of systems rather than isolated events?
Because forces, energy, and motion interact and affect each other within systems.