How dense?

Question 1

What is matter?

Answer 1

Any object that has mass and occupies space

Question 2

What is mass?

Answer 2

The measure of the amount of matter in an object

Question 3

What is weight?

Answer 3

The measure of the amount of force of gravity on an object of a certain mass

Question 4

What is the acceleration due to gravity on Earth?

Answer 4

9.8

Question 5

What is the acceleration due to gravity on the moon?

Answer 5

It is 1/6 of Earth, so 1/6 of 9.8.

Question 6

How to find the weight of a substance?

Answer 6

W = m * g or
Weight = Mass * Acceleration due to gravity

Question 7

What is volume? What are its formulas?

Answer 7

Volume is the measure of the amount of space an object takes up.
Volume = Length * Breadth * Height
V = M/D

Question 8

What is density? What is its formula? What is its unit?

Answer 8

Density is the measure of the amount of mass in a certain amount of space. Its formula is D = M/V and its SI unit is g/cm3 (grams per centimeters cube).

Question 9

What does the Archimedes principle state?

Answer 9

The Archimedes principle states that when an object is immersed in water its apparent loss in weight is equal to the upthrust and is also equal to the weight of the liquid displaced.

Question 10

What is the buoyant force/upthrust?

Answer 10

It is the measure of the upward force a liquid exerts on an object that is submerged.

Question 11

Why do some objects sink and others float (relate it to the buoyant force)?

Answer 11

Objects sink when the weight of the object is greater than the buoyant force. Objects float when the buoyant force is greater than the weight of the object.

Question 12

Describe the relationship between density and volume

Answer 12

Density and volume are inversely proportional. If an object has a large volume compared to its mass, it will have a lesser density

Question 13

Describe the relationship between density and mass

Answer 13

Density and mass are directly proportional. If an object has a large mass compared to its volume it will have a high density.

Question 14

What do fishes have to adjust depth?

Answer 14

Fishes have an air bladder/swim bladder that lets them do this. When they want to go closer to the surface air enters the bladder, increasing volume but only slightly increasing mass.

Question 15

What do sharks have to adjust the depth?

Answer 15

Sharks have oily livers and special types of fins to do this

Question 16

What do submarines do to adjust their depth?

Answer 16

Submarines have ballast tanks to do this. These tanks take in and remove seawater. If a submarine needs to go deeper in the ocean they take in more seawater, which increases its mass while increasing the volume very slightly. This is because when salinity increases density increases.

Question 17

Why is ice less dense than water?

Answer 17

Ice has a crystalline structure and air in between its molecules.

Question 18

What is salinity?

Answer 18

The dissolved salt content of a body of water.

Question 19

Describe the relationship between density and temperature.

Answer 19

As temperature increases density decreases. They are inversely proportional. This is because when we increase temperature atoms get more kinetic energy and intermolecular spaces increase. Cold water is denser so it is at the bottom of the ocean.

Question 20

Describe the relationship between density and salinity

Answer 20

They are directly proportional. When salinity increases density increases. Deeper in the ocean salinity increases and density increases.