Diving Physics

Water is able to conduct heat far more efficiently than air because it is

• less dense than air.

• more dense than air.

• more fluid than air.

• less fluid than air.

Divers are most affected by what form of heat transmission?

• Conduction

• Convection

• Radiation

• All of the above are equally important

Water is able to conduct heat about ______ times faster than air.

• 3200

• 775

• 100

• 20

Refraction is caused by the process of:

• light traveling at different speeds as it passes through different substances.

• water absorbing various wave lengths of light beginning at the red end of the spectrum.

• the changing speed of light due to sunspot activity.

• light traveling at the same speed as sound once it enters water and encounters resistance.

When viewed underwater, objects normally appear ____ by a ratio of about _____ (actual to apparent distance).

• closer/2:1

• further away/4:3

• closer/4:3

• further away/2:1

When viewed underwater, objects tend to be magnified by a factor of about:

• 10%

• 33%

• 50%

• 74%

“Visual reversal” refers to an object’s tendency to appear:

• as a mirror image of itself.

• upside down, as though viewed through a magnifying lens.

• like a photographic negative.

• further away than its actual distance.

The single most important factor affecting the “visual reversal” phenomenon is:

• depth.

• turbidity.

• time of day.

• All of the above are equally important.

Light waves contain _____, while sound waves are comprised of _____.

• heat energy/air

• electromagnetic energy/mechanical energy

• infrared energy/ultraviolet energy

• kinetic energy/potential energy

The density and elasticity of a medium has what effect upon the transmission of sound?

• The denser and more elastic the medium, the better sound is transmitted.

• The denser and more elastic the medium, the poorer sound is transmitted.

• The denser and more elastic the medium, the less sound can be transmitted.

• Density and elasticity of a medium has no effect upon the transmission of sound.