Chapter 11

Question 1

What is pressure

Answer 1

A force exerted over an area

Question 2

What is the formula for calculating pressure

Answer 2

Pressure=force divided by area

Pressure=newtons divided by m2

Question 3

What is the si unit of pressure

Answer 3

Pascal
Pa=1 newton per 1 square meter
Pa=1 n/m2

Question 4

What is a fluid

Answer 4

A material that can easily flow or easily change shape

Liquids and gasses

Question 5

What causes fluid pressure

Answer 5

All of the forces exerted by the individual particles in a fluid combine to make up the pressure

Question 6

What causes air pressure

Answer 6

The weight of the air produces a force

Question 7

How is the pressure on your hand balanced

Answer 7

The pressure of earth’s atmosphere is exerted on your hand in all directions

Question 8

What is the relationship between air pressure and elevation

Answer 8

As elevation increases pressure decreases

Question 9

What is the relationship between water pressure and depth

Answer 9

Water pressure increases with death

Question 10

What instrument is used to measure air pressure

Answer 10

Barometer

Question 11

What is buoyant force

Answer 11

The upward force that is exerted on objects submerged in fluids
Buoyant force acts in the direction opposite to the force of gravity so an object will feel lighter

Question 12

What is Archimedes principle

Answer 12

The buoyant force acting on a submerged object is equal to the weight of the fluid the object displaces

Question 13

What is density

Answer 13

The amount of mass per unit of volume of a substance
Expressed as grams per cubic centimeters
G/cm3
Objects that sink in water are more dense than water
Objects that float in water are less dense than water
Generally all metals are more dense than water wood is less dense than water and rubber is more dense than water

Question 14

What is the formula for calculating density

Answer 14

Mass divided by volume

Question 15

What is pascals principle

Answer 15

When forced is applied to a confined fluid the change in pressure is transmitted equally to all the parts of the fluid
Pressure increases by the same amount throughout a fluid in enclosed space

Question 16

What is the hydraulic system

Answer 16

A device that multiplies force by applying the force to a small area. The increase in pressure is then transmitted to another part of the confined fluid which pushes on a larger surface area
Heavy lifter on the fire truck
The brakes on a car

Question 17

What is bernoullis principle

Answer 17

As the speed of a moving fluid increases the pressure within the fluid decreases
High pressure pushes toward low pressure
Explains how much smoke rises in a chimney a vacuum cleaner works and how a perfume atomizer works

Question 18

How do planes fly

Answer 18

Air moving over the top of a wind moves faster than below the wing
The faster moving air creates low air pressure
Below the wing high pressure is created
High pressure from below the wing pushes up=lift
The differences in air pressure causes lift