Physics 2 HW 11 steps

What is the wavelength of the radio waves broadcast by an FM radio station with a frequency of 103.00 MHz? (Round the final answer to three decimal places.)

1. write what you’re given (frequency:f, speed of light: c)

2. convert MHz → Hz (1 MHz = 10⁶)

3. Rearrange the formula (λ=fc​)

4. Plug in numbers and solve

What is the frequency of the microwaves in a microwave oven? The wavelength is 3.20 cm. (Round the final answer to three decimal places.)

1. Write what you’re (wavelength: λ, speed of light: c)

2. convert cm to m

3. plug into formula f=c/λ

4. solve and convert to GHz (1 GHz → 10⁹ Hz)

How far does a beam of light travel in 1.600 ns?

1. Write what you’re given (time: t, speed of light: c)

2. Convert ns to s (x10^-9)

3. Plug into formula d= vt

4. Solve and convert m → cm

Consider regions of the EM spectrum.

 

In order to study the structure of a crystalline solid, you want to illuminate it with EM radiation whose wavelength is the same as the spacing of the atoms in the crystal (0.130 nm).

What is the frequency of the EM radiation? (You may enter your calculation using scientific notation.)

1. Write what you’re given (wavelength: λ, speed of light: c)

2. convert nm → m (1 nm = 10^-9)

3. Plug into formula f=c/λ and solve

In order to study the structure of a crystalline solid, you want to illuminate it with EM radiation whose wavelength is the same as the spacing of the atoms in the crystal (0.130 nm).

In what part of the EM spectrum (radio, visible, etc.) does it lie?

x rays

The speed of light in a semi-precious stone is . What is the index of refraction of the semi-precious stone? (Round the final answer to three decimal places.)

1. Write what you need (speed of light in a vacuum: c, speed of light in the stone: v)

2. Use the formula n = c/v

3. Plug in and solve

What is the speed of light in a precious stone that has an index of refraction of 1.5711? (You may enter your calculation using scientific notation.)

1. Write what you’re given (index of refraction: n, speed of light: c)

2. Plug into formula v = c/n

3. Solve

When the NASA Rover Spirit successfully landed on Mars in January of 2004, Mars was from the Earth. Twenty-one days later, when the Rover Opportunity landed on Mars, Mars was from the Earth.

How long did it take for a one-way transmission to the scientists on the Earth from Spirit on its landing day?

1. Identify whats given (distance: d, speed of light: c)

2. Fix units (km → m, x10⁹)

3. Use formula t=d/c

4. Plug in and solve

5. Divide by 60 to make seconds into minutes

When the NASA Rover Spirit successfully landed on Mars in January of 2004, Mars was from the Earth. Twenty-one days later, when the Rover Opportunity landed on Mars, Mars was from the Earth.

How long did it take for scientists to communicate with Opportunity on its landing day? 

1. Identify what matters (distance: d, speed of light:c)

2. Convert units (km → m)

3. Write the formula t = d/c

4. Convert to minutes (divide by 60)

The index of refraction of a liquid is 1.540.

What is the speed of light in this liquid? (You may enter your calculation using scientific notation.)

1. Identify the values (n, c)

2. Plug into the formula v = c/n

3. Plug in and solve

The index of refraction of a liquid is 1.540.

What is the wavelength in the liquid of a light wave with a vacuum wavelength of 503 nm?

1. Identify values (λ0​ = wavelength in vacuum, n = index of refraction, λ = wavelength in the liquid)

2. Plug into the formula λ=λ0​​/n

Light of wavelength 642 nm in air passes into window glass with an index of refraction of 1.52.

What is the wavelength of the light inside the glass?

1. identify values (λ0​ = wavelength in air (vacuum, n = index of refraction, λ = wavelength in the material)

2. Plug into λ=λ0​​/n

3. Solve, answer in nm

Light of wavelength 642 nm in air passes into window glass with an index of refraction of 1.52.

What is the frequency of the light inside the glass? (You may enter your calculation using scientific notation.)

1. Recognize the key concept (light goes from air → glass, index of refraction affects speed and wavelength only, so frequency stays the same)

2. Convert wavelength to meters nm→ m (x10^-9)

3. Solve for frequency using f=c/λ

4. Solve and answer is in Hz