Light: wavelength, frequency and energy

Answer Key - Grade 10 Science Worksheet

Circle the best answer, or write your answer on the line.

1. 1.

   Using E = hν with h = 6.626 × 10⁻³⁴ J·s, what energy does a photon of 5 × 10¹⁴ Hz carry, in units of 10⁻¹⁹ J, Ari?

   3.31 × 10⁻¹⁹ J
2. 2.

   Using E = hν with h = 6.626 × 10⁻³⁴ J·s, what energy does a photon of 7.5 × 10¹⁴ Hz carry, in units of 10⁻¹⁹ J, Esme?

   4.97 × 10⁻¹⁹ J
4. 3.

   On the ladder, why is the photon from the big drop blue, Jun?

   • Bigger drops make much longer waves
   • Blue light is slower
   • More energy means higher frequency
5. 4.

   On the strip, a drop gives green light at 550 nm. How big was the drop, Luz?

   Use the picture in question 3.

   • Between the blue and red drops
   • Smaller than the red drop
   • Bigger than the drop for blue light
6. 5.

   What is 500 nm in meters, Milo?

   • 5.00 × 10² m
   • 5.00 × 10⁻⁷ m
   • 5.00 × 10⁻⁹ m
7. 6.

   What does 1 Hz mean, Noah?

   • One wave each second
   • One joule each second
   • One meter each second
8. 7.

   Why does E = hν give an answer in joules, Pia?

   • h has units of meters
   • J·s × 1/s leaves J
   • Hz are a kind of joule
9. 8.

   Which visible color's photons carry the most energy, Ren?

   • Yellow
   • Violet
   • Red
10. 9.

    Light of 300 nm is compared with 600 nm. How do their photon energies compare, Tala?

    • The 600 nm photon has twice as much
    • The 300 nm photon has twice as much
    • They are equal
11. 10.

    A red lamp is made brighter. What happens to the energy of each photon, Zee?

    • It rises
    • It falls
    • It stays the same