Ch 6 Review Game

Which of the following has the shortest wavelength?

• microwaves

• UV rays

• Infrared

• the color blue

• radio waves

Which of the following has the lowest energy?

• The color yellow

• The color blue

• The color purple

• The color orange

Calculate the energy of the photons in a type of electromagnetic radiation if the frequency is 4.50 x 10¹⁸ Hz.

• 2.98 x 10¹⁵ joules

• 1.47 x 10^-52 joules

• 6.79 x 10⁵¹ joules

• 2.98 x 10^-15 joules

• 6.67 x 10^-11 joules

Answer explanation

To calculate the energy of photons in electromagnetic radiation, we use the formula E = h * f, where E is the energy, h is Planck's constant (6.626 x 10^-34 Js), and f is the frequency. Given a frequency of 4.5 x 10^18 Hz, we multiply by Planck's constant to find the energy: E = (6.626 x 10^-34 Js) * (4.5 x 10^18 Hz) = 2.98 x 10^-15 joules. Therefore, the correct option is 2.98 x 10^-15 joules.

What is a photon?

• When radiation bursts through electric waves

• The emission of electrons from a metal caused by light striking the metal

• The rate at which a wave's energy flows through a given unit of area

• Particles of light, also called packets of light energy

Answer explanation

A photon is a particle that represents a packet of electromagnetic energy. It is the elementary carrier of electromagnetic radiation, such as light. The other options refer to specific processes or measurements related to electromagnetic waves, but they do not define a photon itself.

Calculate the wavelength of light that has the following frequency:

5.2 x 10¹² s^-1

• 5.8 x 10^-5 m

• 5.8 x 10^-7 m

• 5.19 x 10¹⁴ m

• 1.56 x 10²³ m

• 1.73 x 10⁴ m

Answer explanation

To solve the problem, we use the given equation, c = λν. We are given the frequency (ν) as 5.2 x 10^12/s and the speed of light (c) as 3.00 x 10^8 m/s. To find the wavelength (λ), we can rearrange the equation as λ = c/ν. Plugging in the values, we get λ = (3.00 x 10^8) / (5.2 x 10^12), which results in λ = 5.8 x 10^-5 m. Therefore, the correct answer is 5.8 x 10^-5 m.

When atoms _____________ energy, their electrons move to higher energy levels. These electrons _____________ energy by emitting light when they return to lower energy levels.

• lose, absorb

• absorb, lose

• lose, lose

• absorb, absorb

Answer explanation

When atoms absorb energy, their electrons get excited and move to higher energy levels. As they return to their original, lower energy levels, they lose energy by emitting light. Thus, the correct choice is 'absorb, lose'.

A beam of light has a wavelength of 615 nm. What is the color of this light?

• purple

• blue

• green

• yellow

• red

A beam of light has a wavelength of 465 nm. What is the color of this light?

• purple

• blue

• green

• yellow

• red

A beam of light has a wavelength of 615 nm. What is the frequency of this light?

• 4.88 x 10¹⁴ Hz

• 4.88 x 10^-4 Hz

• 0.0488 Hz

• 2.05 x 10^-15 Hz

• 4.88 x 10⁵ Hz

A broadcasting station emits a signal at a frequency of 102.5 MHz. What is the wavelength of this signal in meters?

(MHz = 10⁶ Hz)

• 2.93 m

• 0.293 m

• 2.93 x 10^-7 m

• 2.93 x 10⁶ m