Bennett Mechanical Test Acoustics and Optics 2 — Questions and Answers
Question 1: Sound travels fastest through which medium?
- Steel (Correct answer)
- Air
- Water
- A vacuum
Correct answer: Steel
Sound moves fastest through dense solids like steel because tightly packed molecules transmit vibrations quickly.
Question 2: When light passes from air into water, it bends because the light:
- Slows down (Correct answer)
- Speeds up
- Stops briefly
- Changes color
Correct answer: Slows down
Light slows when entering denser water, and this speed change bends (refracts) the ray.
Question 3: An echo is produced when sound waves:
- Reflect off a surface (Correct answer)
- Pass through a wall
- Are absorbed completely
- Speed up in air
Correct answer: Reflect off a surface
An echo is sound reflecting off a hard surface and returning to the listener.
Question 4: A higher-frequency sound wave is heard as a sound with a:
- Higher pitch (Correct answer)
- Lower pitch
- Greater loudness
- Slower speed
Correct answer: Higher pitch
Frequency determines pitch, so higher frequency means a higher pitch.
Question 5: A convex (converging) lens is commonly used to:
- Magnify objects (Correct answer)
- Spread light apart
- Block all light
- Reflect images
Correct answer: Magnify objects
A convex lens converges light to a focal point and can magnify objects.
Question 6: Which property of a sound wave determines its loudness?
- Amplitude (Correct answer)
- Frequency
- Wavelength
- Speed
Correct answer: Amplitude
Greater amplitude carries more energy and is heard as a louder sound.
Question 7: A flat mirror produces an image that is:
- Reversed left-to-right (Correct answer)
- Upside down
- Magnified
- Blurry
Correct answer: Reversed left-to-right
A flat (plane) mirror produces an upright, same-size image that is laterally reversed.
Bennett Mechanical Test Acoustics and Optics 2
Sound travels fastest through which medium?