1. Radio telescopes beam radio waves into space. To calculate the speed of the radio waves in space, which additional piece of
information, if any, is necessary? (1 point)
The strengths of the electric and magnetic fields.
O The frequency of the radio waves.
O The wavelength of the radio waves.
O None (the speed is a known constant).
2. As explained by the theory of quantum electrodynamics, light is best described as
Both a wave and particles.
O Particles, not a wave.
O A wave, not particles.
3. A physicist is investigating a beam of laser light of wavelength 550 nm. The light strikes a target that is 189 meters away
from the source of the light. What is the travel time of the light from the source to the target? Let the speed of light c =
3.00 x 10^8 m/s. (1 point)
4.23 x 10-7 s
6.30 x 10^-7s
1.83 x 10^-6s
O 3.47 x 10^-45Science