CH 8 Test Materials & EXTRAS

Question 1

Describe 3 ways of determining the volume of an object

Answer 1

For a solid with a regular shape, you can measure its length, width, and height. The volume is the product of these three values.

For a solid with an irregular shape, you can use the method of displacement.
-using a graduated cylinder
- pouring water inside and measuring its volume
- placing an object inside and measuring the total volume

If the object is too large to fit in a graduated cylinder
- use an overflow can
- pour water inside and measure its volume
- place object inside and measure volume of displaced water (that flowed out of spout)

Question 2

Describe the relationship between weight, mass, and volume.

Answer 2

Mass is the amount of matter in an object.
Weight is the force of gravity on an object.
Volume is the amount of space an object takes up.

Question 3

Pure water is most dense at?

Answer 3

pure water is most dense at 4 degrees celcius

Question 4

What is weight? What happens with objects with more mass?

Answer 4

Weight is how strongly an object is pulled by gravity. Objects with more mass experience a stronger pull, so they weigh more.

Question 5

What is the formula for Volume?

Answer 5

Volume = l x w x h

Question 6

What is displacement and how does it work

Answer 6

Displacement is to take the place of
-using a graduated cylinder
- pouring water inside and measuring its volume
- placing an object inside and measuring the total volume
- subtracting the total volume from its original volume to find the displacement

Question 7

What is the formula for Density?

Answer 7

Density = mass (g)
volume

Solids/Liquids —> g/ml g/cm3
Gases —> kg/m3

Question 8

What is buoyancy and how does it work?

Answer 8

Buoyancy is the upward force that a fluid exerts on an object. It determines whether an object sinks or floats.

Question 9

How is density related to buoyancy

Answer 9

Density and buoyancy are related if something is less dense than the fluid it’s in, it will float. If it’s denser, it will sink. The denser something is compared to the fluid, the more likely it is to sink.

Question 10

How do you determine whether an object will sink or float?

Answer 10

To determine whether an object will sink or float, you can compare its density to the density of the fluid it’s placed in. If the object is less dense than the fluid, it will float. If it’s denser, it will sink.

Question 11

What does it mean if something is more dense?

Answer 11

If something is more dense, it means that it has more mass packed into a given volume.

Question 12

What does it mean if something is less dense?

Answer 12

If something is less dense, it means that it has less mass packed into a given volume.

Question 13

What happpens when a ship or submarine needs to become more and less buoyant?

Answer 13

When a ship or submarine needs to become more buoyant, it fills the ballast tanks with air, which increases the overall volume and decreases the density of the vessel. This allows it to float higher in the water. On the other hand, when the vessel needs to become less buoyant, it fills the ballast tanks with water, which increases the weight and decreases the volume, causing it to sink lower in the water.

Question 14

What is the meniscus and how should it be used when measuring the volume of water in a graduated cylinder?

Answer 14

The meniscus is the curved surface of a liquid in a container, like a graduated cylinder. To accurately measure the volume of water in a container you should read the bottom of the curved water surface. This method helps to avoid parallax error and ensures a more precise measurement.

Question 15

Use the particle theory to explain density.

Answer 15

All matter is made up of tiny particles. When these particles are closely packed together, the object or material is denser because it has more mass in a given volume.

Question 16

What is meant by positive buoyancy, neutral buoyancy, and negative buoyancy?

Answer 16

Positive buoyancy occurs when an object or substance is less dense than the fluid it’s in, causing it to float.

Neutral buoyancy happens when the object’s density is equal to the fluid’s density, resulting in it neither sinking nor floating.

Negative buoyancy occurs when the object is denser than the fluid, causing it to sink.

Question 17

What are some of the advantages and disadvantages of determining volume by the water displacement method?

Answer 17

Advantages: It works well for irregularly shaped objects.
- It can be used for both solids and liquids.

Disadvantages: The potential for water spillage.
- The need for a container large enough to fully submerge the object.

Question 18

Why must hot air balloons carry a heat source with them?

Answer 18

Hot air balloons must carry a heat source, typically a burner, to maintain the temperature of the air inside the balloon. Heating the air makes it less dense than the surrounding air, creating the buoyant force that allows the balloon to float.

Question 19

Describe two positive applications of buoyancy and two negative effects of buoyancy.

Answer 19

Buoyancy has positive uses such as keeping people afloat in water using life jackets and flotation devices. Submarines and ships are also designed to stay afloat using buoyancy.

The negative effects of buoyancy can lead to ships sinking due to leaks or damage. Additionally, objects may become lost or hard to retrieve in water.

Question 20

What happens if you adjust the amount of water or air in Ballast Tanks?

Answer 20

By adjusting the amount of water or air in the ballast tanks, ships and submarines can control their buoyancy and maintain stability while navigating through different water conditions.

Question 21

What happens if you compare the sizes of two objects made of the same stuff?

Answer 21

If you compare the sizes of two objects made of the same stuff, the larger object will have more mass.