Wave and light

Question 1

What is radiation?

Answer 1

Heat transfer by the emission of electromagnetic waves which carry energy away from the emitting object

Radiation occurs without any temperature difference.

Question 2

How does heat transfer occur?

Answer 2

Through radiation, conduction, and convection

Radiation can occur even between cold objects.

Question 3

What is the wavelength range visible to human eyes?

Answer 3

A limited range of wavelengths

At lower temperatures, waves emitted by heat sources are often invisible.

Question 4

What happens to radiation at extremely high temperatures?

Answer 4

It is clearly perceived by human eyes

Example: The sun at 6000 K.

Question 5

What is the relationship between wavelength and frequency?

Answer 5

Longer wavelength = lower frequency

This relationship is fundamental in wave theory.

Question 6

What did Max Planck propose about light?

Answer 6

Light must be quantized in discrete particles emanating from a source

These particles vibrate at a frequency corresponding to their energy.

Question 7

What is an electromagnetic wave composed of?

Answer 7

An electric wave and a magnetic wave traveling together at right angles

All light waves travel at the same speed in a vacuum.

Question 8

What is the speed of light in a vacuum?

Answer 8

3.00 × 10^8 m/s

The speed of a wave is the product of its frequency and wavelength.

Question 9

What is the Heisenberg Uncertainty Principle?

Answer 9

We can never know exactly both the position and momentum of an electron simultaneously

Electrons can be observed as either particles or waves, but not both at the same time.

Question 10

What is the ground state of an electron?

Answer 10

Lowest energy level

Electrons in the ground state cannot lose any energy.

Question 11

What is electron transition?

Answer 11

Movement of electrons between energy levels

Energy levels of atoms are quantized, not continuous.

Question 12

What does the Bohr Model propose about electrons?

Answer 12

Electrons exist in discrete orbits based on their energy

When an electron jumps from one orbit to a lower orbit, it emits energy in the form of a photon.

Question 13

What is the photoelectric effect?

Answer 13

Electrons are emitted from a metal surface when ultraviolet light shines on it

It advanced the understanding of light as containing photons.

Question 14

What is the de Broglie equation?

Answer 14

λ = h/mv

Used to describe the wave properties of matter, specifically electrons.

Question 15

What is Planck’s constant?

Answer 15

6.626 × 10^-34 J·s

It is a universal constant used in quantizing energy.

Question 16

Fill in the blank: The energy of a photon is given by the formula E = hν, where h is _______.

Answer 16

Planck’s constant

Question 17

True or False: Light of a specific color has a specific wavelength and frequency.

Answer 17

True

Question 18

What are the properties of waves?

Answer 18

Wavelength, Amplitude, Frequency

Wavelength is the distance between peaks, amplitude is the height, and frequency is the number of cycles per second.

Question 19

What is line spectra?

Answer 19

Specific patterns of visible, colored lines emitted by excited atoms

These can be used to identify the atom.

Question 20

What happens to the wavelength of larger particles?

Answer 20

The larger the particles, the smaller the wavelengths

Macroscale objects have such small wavelengths compared to their mass that we never notice the wave nature in motion.