define
pendulum
bob
amplitude
oscillation
http://www.google.com/#q=dictionary
Glad that is settled :)
To answer your question, let's break down each term:
1. Pendulum: A pendulum is a weight suspended from a fixed point that is free to swing back and forth under the influence of gravity. It consists of a long string or rod called the "pendulum arm" or "pendulum rod" and a mass at the end called the "bob."
2. Bob: In the context of a pendulum, the bob refers to the mass attached at the end of the pendulum arm. It can be any solid object that has weight, such as a metal ball or a wooden block. The bob swings back and forth when the pendulum is in motion.
3. Amplitude: The amplitude of a pendulum refers to the maximum displacement or distance that the bob moves from its equilibrium position in either direction. It is usually measured from the central point of the pendulum's swing to the highest or lowest point it reaches.
4. Oscillation: Oscillation refers to the repetitive back-and-forth movement exhibited by a pendulum, with the bob swinging alternatively in one direction and then in the opposite direction. The motion of a pendulum is considered an example of an oscillatory motion.
If you have any specific questions about these terms or would like further explanation, feel free to ask!