1. Acoustics, physical concepts

What does acoustics primarily study?

• Brain responses to sound

• Sound production, transmition, perception

• Hearing disorders

• Sound amplification in hearing aids

Answer explanation

Acoustics is a physical branch whicgh seals with the study of sound: production, transmittion and perception

Which of the following is not a fundamental physical quantity?

• Mass

• Time

• Force

• Length

Answer explanation

The basic physical quantities are mass, time and length. All other physical quantities are derived from combinations of these three

The unit of time is

• Second

• Minute

• Hour

• Millisecond

Which statement about mass and weight is correct?

• Weight remains constant in all locations

• Mass is constant; weight depends on gravity

• Mass and weight always change together

• Mass is measured in newtons

Answer explanation

Mass is constant; weight depends on gravity because mass depends on density, and the density is constant. While weight ais affected by gravity changing

If two objects have the same size but different masses. What can you conclude?

• They must be made of the same material

• Their densities are different

• They have different lengths

• They weigh the same

In the MKS system, which units are used for mass and length?

• Gram and centimeter

• Pound and inch

• Dyne and millimeter

• Kilogram and meter

Answer explanation

MKS = Meter. Kilogram, second

The CGS system uses which units for force and work?

• Newton and joule

• Dyne and erg

• Pascal and watt

• Calorie and volt

Answer explanation

Force unit is dyne = 1g*cm/s2 while work unit is erg = dyne*cm

A 5 kg object weighs less on the moon than on earth. Why?

• The moon has a stronger magnetic field

• The object's density changes

• The moon has weaker gravity

• The object's mass is reduced

Answer explanation

Mass is constant; weight depends on gravity because mass depends on density, and the density is constant. While weight ais affected by gravity changing. The gravity on Earth is more than the gravity on Moon

Which of the following units are derived, not fundamental?

• Hertz, volt, second

• Gram, joule, dyne

• Gram, centimeter, second

• Newton, joule, dyne

All of the following are fundamental physical quantities EXCEPT

• Time

• Pressure

• Mass

• Length