Waves Science Test

Vocab

Linear Motion

The movement of an object from place to place without repeating.

Harmonic Motion

An object moves back and forth around an equilibrium position - multiple cycles are repeated over and over.

Oscillator

A system in harmonic motion.

Pendulum

A weight suspended from a fixed point so that it can swing freely back and forth under the influence of gravity.

What must a pendulum have?

A fixed pivot point, a mass, a string/wire

Cycle

one complete repetition of a wave's pattern, moving from a starting point, up to its highest point (crest), down through its rest (equilibrium) position to its lowest point (trough), and back to the starting point.

Period

The time it takes to complete one cycle.

Frequency

The number of cycles an oscillator makes per second.

Period and Frequency are…

Inversely related

Hertz (Hz)

Unit of 1 cycle per second.

What does Hertz (Hz) measure?

Frequency

Amplitude

Describes the size of the cycle. It’s the distance from equilibrium to the highest point on the graph.

Damping

Gradual loss of amplitude of an oscillator due to friction.

Unstable system

Forces act to pull the system away from equilibrium when disturbed.

Stable equilibrium

Restoring forces pull the system toward equilibrium.

Restoring force

Any force that always acts to pull the system back toward equilibrium.

Inertia

The natural tendency of an object to resist change in its state of motion.

What does inertia cause to an oscillator?

Inertia causes an oscillator to go past equilibrium

Phase

Where the oscillator is in the cycle.

natural frequency

The frequency at which systems tend to oscillate when disturbed.

analog signal

Any continuous, time-varying physical signal that represents another quantity in a smooth and proportional way.

What type of signal is shown?

Analog signal

Digital signal

A replica of an analog signal represented using a sequence of discrete, finite values, most commonly in the binary code.

Refraction

The bending of a wave as it passes from one medium to another.

What is the restoring force of a pendulum?

Gravity

Of the three things you can change, (length, mass, angle), which one has the biggest effect on the pendulum?

Length

What is Newton’s 1st law?

An object in motion stays in motion unless acted upon by an outside force.

What is the law of reflection?

When an object hits a surface, its angle of incidence will equal the angle of reflection.

Mass

Mass is the quantitative measurement of an object’s inertia.

What type of signal is shown?

Digital signal