19. a) What is a wave motion? b) A wave is represented by the equation
y = 2sint(0.5x – 200t), where all
distances are measured in cm and time in
second. For this wave, calculate its:
i) frequency
ii) wavelength
iii) speed

Explanation:

Wave motion, propagation of disturbances—that is, deviations from a state of rest or equilibrium—from place to place in a regular and organized way. Most familiar are surface waves on water, but both sound and light travel as wavelike disturbances, and the motion of all subatomic particles exhibits wavelike properties. The study of waves therefore forms a topic of central importance in all physical science and engineering.

the earths atmosphere is made up of nitrogen and oxygen. solids can turn into gasses through a process called sublimation. sublimation is the transition of a substance directly from the solid to the gas phase, without passing through the intermediate liquid phase.

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