Home Chapter 27 Practice Questions

# Practice Questions

This activity contains 27 questions.

## At what temperature would a heated body appear red?

 1000 K 3000 K 6000 K 10000 K

## What is the energy in eV of a microwave photon of wavelength, λ, 3 cm?

 4.1 x 10-5 eV 4.1 x 10-3 eV 4.1 eV 410 eV

## What is the energy in eV of a red photon of wavelength λ = 750 nm?

 4.1 x 10-5 eV 1.7 eV 2.9 eV 410 eV

## What is the energy in eV of a UV photon of wavelength λ = 300 nm?

 4.1 x 10-2 eV 4.1 eV 41 eV 410 eV

## What is the energy in eV of a X-ray photon of wavelength λ = .3 nm?

 4.1 x 105 eV 4.1 x 104 eV 4.1 x 103 eV 410 eV

## How many of the X-ray photons in Question 5 must strike a surface in one second to deliver power of 1 x 10-12 W?

 1 1524 20000 4 x 108

## How many of the microwave photons in Question 2 must strike a surface in one second to deliver power of 1 x 10-12 W?

 4.1 x 105 1.5 x 107 1.5 x 10 1.5 x 1011

## What wavelength photon would produce an (average) intensity of 1 W/m2 with only one photon striking each 1 x 10-12 m2 of the surface per second?

 2 mm 2 nm 2 pm 200 fm

## What type of radiation has the wavelength given by Question 8?

 gamma ray X-ray infrared radio wave

## A metal surface has a work function of 2.5 eV. What color light must hit it for electrons to be emitted?

 red green dark blue violet

## A 450 nm wavelength photon strikes the metal surface in Question 10. What is the maximum energy of the emitted electrons?

 0.26 eV 0.51 eV 2.76 eV

## What is the Compton wavelength?

 2.1 nm 2.43 pm 2.45 fm 27 fm

## A 8300 eV photon Compton scatters at 0 degrees. What is the wavelength of the scattered photon?

 0.14 nm 0.15 nm 0.16 nm 0.17 nm

## A 0.15 nm photon scatters at 90 degrees. What is the wavelength of the scattered photon?

 0.1476 nm 0.15 nm 0.1515 nm 0.1524 nm

## What is the energy of the scattered photon in Question 14?

 40 eV 63 eV 136 eV

## A gamma ray photon creates an electron-positron pair and the products have a total kinetic energy of 0.2 MeV. What was the wavelength of the photon?

 0.8 pm 1.0 pm 1.2 pm 1.2 fm

## The positron in the above question slows down and is annihilated by an electron creating two identical photons going in opposite directions. What is the wavelength of these photons?

 1.0 pm 1.2 pm 2.0 pm 2.4 pm

## What is the wavelength, λ, associated with a 1 gm B-B traveling at 10 m/s?

 2 x 10-5 m 6.6 x 10-5 m 2.8 x 10-30 m 6.6 x 10-32 m

## What is the wavelength, λ, of an electron traveling at 2 x 106 m/s?

 2 x 10-5 m 3.6 x 10-8 m 3.6 x 10-10 m 2 x 10-25 m

## What is the wavelength, λ, of a proton traveling at 2 x 106 m/s?

 2 x 10-13 m 2 x 10-14 m 2 x 10-15 m 4.8 mm

## What is the wavelength of a photon with the same momentum as the the proton in the previous question?

 2 x 10-12 m 2 x 10-13 m 2 x 10-14 m 2 x 10-15 m

## What is the shortest wavelength in the Balmer series?

 0.15 microns 0.36 microns 0.45 microns 0.66 microns

## What is the longest wavelength in the Balmer series?

 0.15 microns 0.36 microns 0.45 microns 0.66 microns

## What is the maximum energy for the Bohr atom?

 - infinity - 13,6 eV + infinity zero

## How much energy in Joules does it take to excite a hydrogen atom into its first excited state?

 10.2 J 1.6 x 10-19 J 1.63 x 10-18 J 3.4 eV

## What temperature in kelvin would be needed for the random kinetic energy of hydrogen atoms to equal the answer to the previous question?

 800 K 7300 K 10000 K 79000 K

## What state (n = ?) would the Bohr atom be in to have a diameter of 1 mm?

 124 2700 3074 4348