Select all the substances that can transmit sound waves.
a. air
b. wood
c. water
d. ground
e. oxygen gas
f. empty space

Assuming weightless pulleys and 100% efficiency, what is the minimum input force required to lift a 120 n weight using a single fixed pulley?

What type of light does this light bulb produce most (i.e. at what wavelength does the spectrum have maximum intensity)?

Identify the theory that can be used to explain each phenomenon. answers diffraction: wave theory interference: wave theory reflection: both particle and wave theories refraction: both particle and wave theories