8 EW Ch 3 Complete

4) The lowest point of a wave is the

• crest.
• wavelength.
• trough.
• frequency.

5) As a wave nears shore, the wave height increases and the wavelength

• decreases.
• increases.
• stays the same.
• doubles.

6) When a tsunami hits the shore, it can be very destructive because of its large

• sandbar.
• trough.
• wave height.
• frequency.

7) In which ocean are tsunamis most common?

• Atlantic
• Pacific
• Indian
• Arctic

8) A rush of water that flows rapidly back to sea through a narrow opening is called a

• longshore drift.
• breaker.
• tsunami.
• rip current.

9) To reduce erosion along a strip of beach, you might build a short wall called a

• dune.
• barrier beach.
• groin.
• sandbar.

10) Dunes reduce beach erosion because

• they cause the tides to go higher.
• they cause waves to break offshore.
• the roots of dune plants hold sand in place.
• they prevent people from walking on the beach.

1) The size of a wave is NOT affected by the

• length of time the wind blows across the water.
• salinity of the water.
• strength of the wind.
• distance the wind blows across the water.

3) The horizontal distance between wave crests is the

• frequency.
• wavelength.
• trough.
• wave height.

1) Salinity is a measure of which of the following in water?

• carbon dioxide
• oxygen
• dissolved salts
• sand