Density and Buoyancy

True or False

100

The density of a kilogram of iron is less than the density of 1 gram of iron.

F- greater than

200

Pascal's principle explains the relationship between density and buoyancy.

F- Archimedes Principal

300

You can use a balance to measure the volume of a liquid.

F- Graduated cylinder

400

A person standing on his or her toes and the same person standing flat footed exert the same amount of pressure on the ground

F- Different amounts

500

A fish with a mass of 5 kg and swimming at a depth of 5 m experiences the same buoyant force as a fish with the same mass swimming at a depth of 10 m.

True

Multiple Choice

100

____ is a physical property.

a.Oxidation

b.Flammability 

c.Density

d.Combustibility

c- Density

200

Density depends on ____. 

a.weight

b.mass and volume 

c.mass 

d.volume

b- mass and volume

300

The ____ is a unit of force. 

a.pascal 

b.newton 

c.atmosphere

d.kilopascal

b- Newton

400

Archimedes' Principle helps to explain the relationship between ____.

a.kinetic energy and density

b.pressure and density 

c.temperature and density

d.buoyancy and density

D- buoyancy and density

500

A cork is able to float on water because it is ____. 

a.a crystalline solid 

b.small in size 

c.equal in density to water 

d.less dense than the water

D- Less dense than water

Multiple Choice 2

100

Which statement best explains why a piece of aluminum foil that is tightly crumpled into a ball sinks while the same piece of foil floats when it is loosely formed into a ball?

a.Water can seep into the loosely crumpled ball.

 b.The foil ball weighs more when it is tightly crumpled.

c.The density of aluminum changes when its shape changes.

d.The loosely crumpled ball has less volume than the tighly crumpled ball

c.The density of aluminum changes when its shape changes.

200

Lee has three identical 1-L bottles. One is filled with water, another is filled with air, and the third bottle is filled with soil. What is the same about all three bottles?

a.density

b.mass 

c.volume

d.weight

c- Volume

300

A box sinks when placed in water. What could you change about the box to make it float? 

a.density 

b.atmospheric pressure 

c.temperature

d.Archimedes’ principle

A- Density

400

Valerie has a balloon filled with air. When she places it on the surface of a pond, the balloon floats. What would happen to the balloon if Valerie filled the balloon with sand and then placed it on the pond’s surface? 

a.The balloon would sink. 

b. The balloon would float in the air. 

c.The balloon would burst.

d.The balloon would float in the water.

A- The balloon would sink

500

Which is the upward force on an swimmer that balances the downward force of gravity and keeps the swimmer from sinking? 

a.atmospheric pressure

b.density 

c.buoyant force 

d.pascal

c- buoyant force

Short Answer

100

Explain why a dry sponge will initially float when placed on the surface of water but will sink after a while.

Air holes in a dry sponge make sponge initially less dense than the water, when sponge absorbs water, its density increases and it sinks.

200

Explain how a ship made of materials that are much denser than water is able to float on water.

Cargo ships generally have large, wide bottoms allowing a greater amount of surface to be in contact with the water. If force is exerted over a larger area, the pressure against the water decreases.

300

Which would exert more pressure on the floor, standing flat-footed or standing on your toes?

Standing on your toes exerts more pressure on the floor.

400

You are trying to float in a swimming pool. Would it be better if you inhaled as much air as possible or exhaled as much air as possible?

It would be better to inhale as much air as possible to float in a pool. By filling your lungs with air, your body becomes less dense and therefore floats in water.

500

A diver wearing all her equipment has a mass of 70 kg. The mass of the water she displaces is 78 kg. Will the diver sink or float?

The diver will sink.

Vocabulary

100

the downward force acting on something in a fluid

What is gravity

200

a state of matter with enough energy to overcome the attractive forces within its atoms, composed of positively and negatively charged particles 

What is plasma

300

any substance that has no definite shape and is able to flow

What is fluid

400

upward force exerted by a fluid on any object in the fluid

What is buoyant force

500

a principal that states that the buoyant force acting on an object is equal to the weight of the fluid displaced by the object.

What is the Archimedes' Principle