Question

Find the word that names a necessary part of the underlined word. \underlineVibration

• A. Motion
• B. Electricity
• C. Science
• D. Sound
• E. Electron

Hint:

To solve "Necessary Part" questions, ask yourself: "Can I have X without Y?" Can you have a vibration without sound? Yes. Can you have a vibration without motion? No. The "No" answer identifies the necessary part.

Answer 1

The Correct Option is A

Concept: In "Necessary Part" problems, we look for the one element that must exist for the target word to be possible. While other options might be related to or caused by the word, the necessary part is the fundamental requirement.
Step 1: Define the underlined word.
Vibration is defined as a rapid back-and-forth movement or oscillation of a particle or elastic solid around an equilibrium point.

Step 2: Evaluate each option for necessity.
• Motion: A vibration is, by definition, a type of repetitive motion. Without motion, vibration cannot exist. (Necessary)
• Electricity: Many vibrations are caused by electric motors, but many are not (e.g., a plucked guitar string). Not a requirement.
• Science: This is a category under which we study vibrations, not a component of the vibration itself.
• Sound: Vibrations often create sound waves, but vibrations can occur in a vacuum or at frequencies humans cannot hear. Sound is a result, not a necessary part.
• Electron: While everything is made of atoms and electrons, an electron itself is not a specific "part" that defines the action of vibrating.

Step 3: Conclusion.
Since motion is the fundamental state of any vibration, it is the necessary part.