Science

Which of these materials is least useful as an insulator?

• Cardboard

• Aluminum

• Rubber

• Plastic

A bolt is not attracted to a magnet and sinks to the bottom of maple syrup. Which of these best describes some of the bolt's physical properties?

• The bolt is magnetic and has the same density as the maple syrup.

• The bolt is nonmagnetic and more dense than the maple syrup.

• The bolt is nonmagnetic and less dense than the maple syrup.

• The bolt is magnetic and less dense than the maple syrup.

Which two objects are most likely less dense than water?

• Wood block and metal paper clip

• Plastic ball and glass marble

• Metal paper clip and glass marble

• Wood block and plastic ball

A teacher wears protective gloves to lift a metal pan filled with boiling water from a hot plate. Why are the protective gloves necessary?

• The metal pan creates thermal energy.

• The metal pan insulates thermal energy.

• The metal pan conducts thermal energy.

• The metal pan reduces thermal energy.

Foam cup, keys, and coins fell into a swimming pool. Which of the following explains a useful method for removing some of these objects?

• The keys and coins are less dense than water, so they can be easily picked up off the bottom of the pool by divers.

• The foam cups have the same density as water, so they can be crumbled up for removal by the pool filter.

• The foam cups are less dense than water so they can be removed from the surface with a pool cleaning net.

• The keys are coins have the same density as water, so they can be washed away when the pool is drained.

A salad dressing is made from oil, vinegar, and spices. Why would you need to shake the salad dressing well before pouring it onto food?

• Vinegar and oil have different densities.

• Vinegar and oil easily form a solution.

• Vinegar and oil both contain water.

• Vinegar and oil are both liquids.