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The Ultimate Sharks and Magnets Quiz
by Staff
Several innovative companies around the world have developed devices based on the idea of repelling sharks with magnets. Do they work? Check out our quiz and learn more about sharks and magnets.

Which of the following have been sold as shark repellants?

  • sunscreens
  • disguises
  • both of the above

Tonic immobility is a condition that occurs when a fish lies on its:

  • right side
  • left side
  • back

What happens when you drop a magnet in the water near a shark?

  • Nothing happens.
  • The shark swims away.
  • The shark jumps out of the water.

When you mix salt water and charged metals, you get a weak electrical:

  • field
  • zone
  • area

The special pores located around the snouts of many shark species are called _____ of Lorenzini.

  • nostrils
  • pores
  • ampullae

Electrical impulses are carried through the _____ in the salt water in the ocean.

  • ions
  • neutrons
  • electrons

Sharks can sense changes in underwater electrical fields through their ampullae of Lorenzini. Stronger electric fields caused by _____ may overwhelm their senses

  • sound waves
  • radio waves
  • magnets

Which company applied for a United States patent for installing Lanthanide electropositive metals into scuba flippers and other items to act as a shark repellant.

  • SharkProtector
  • SharkDefense
  • SharkAway

What is the major problem with Eric Stroud's invention that uses magnets to repel sharks?

  • You would need too many magnets.
  • The sharks will eat the magnets.
  • The magnets will fall off in the water.

Sharks are known to pursue their prey single-mindedly. How might this influence the effectiveness of a magnetic shark repellant?

  • The sharks will definitely back off.
  • The sharks will never back off.
  • The sharks will possibly back off.

What percent of the world's sharks are on the verge of extinction?

  • 20 percent
  • 30 percent
  • 40 percent

SharkDefense suggests using electropositive metals on _____ in an attempt to keep sharks away from commercial fishing bait.

  • fishing hooks
  • fishing nets
  • fishing lines

Which company is studying the feasibility of using magnetic fences to keep sharks away?

  • Sea Magnetics
  • Shark Magnetics
  • Ocean Magnetics

During which war did the United States Navy seek to develop an effective shark repellant?

  • World War I
  • World War II
  • the Vietnam War

During the 2000 Summer Olympics in _____, Australia, divers wore gadgets called Protective Oceanic Devices (PODs) to ward off sharks.

  • Melbourne
  • Sydney
  • Brisbane