<span> </span>J. J. <span>Thomson discovered cathode rays</span>
1. Frequency: 
The frequency of a light wave is given by:
where
is the speed of light
is the wavelength of the wave
In this problem, we have light with wavelength
Substituting into the equation, we find the frequency:
2. Period: 
The period of a wave is equal to the reciprocal of the frequency:
The frequency of this light wave is (found in the previous exercise), so the period is:
False. Inertia and mass is not described in Newton’s second law of motion but in Newton’s first law of motion. Newton’s first law of motion or sometimes referred to as the law of inertia. In Newton’s first law indicates that an object at rest will remain at rest unless acted by an unbalanced force. An object in motion continues in motion with the same speed and in the same direction unless acted upon by an unbalanced force.
The correct choice is
B. sublimation, then condensation
Sublimation is the name of the process where a solid directly converts into gas on heating. on heating solid crystals of iodine directly change into gas. hence this is sublimation.
condensation is the process where gas is converted into liquid on cooling.
here iodine gas is being converted into droplets on reducing the temperature. hence this is condensation.
