Physics: Energy, Work and Simple Machines

Question 1

Efficiency

Answer 1

can be calculated by comparing a machine’s output work to its input work

Question 2

Machine

Answer 2

A device that changed the magnitude or direction of a force

Question 3

Compound Machine

Answer 3

Consists of two or more simple machines linked so that the resistance force of one machine becomes the effort force of the second machine

Question 4

Resistance Force

Answer 4

The force exerted by a machine

Question 5

Watt

Answer 5

A unit of power defined as 1 joule per second

Question 6

Effort Force

Answer 6

The force exerted by a person on a machine

Question 7

Work-energy theorem

Answer 7

States that the work done on an object equals the change in kinetic energy of the object

Question 8

Energy

Answer 8

The ability of an object to produce a change in itself or its surroundings

Question 9

Kinetic energy

Answer 9

The energy that results from the motion of an object

Question 10

Power

Answer 10

The rate of doing work

Question 11

Mechanical advatage

Answer 11

The ratio of resistance force of a machine to its effort force

Question 12

Joule

Answer 12

The SI unit for work

Question 13

Ideal Mechanical Advantage

Answer 13

To calculate you compare the effort distance to the resistance distance

Question 14

Work

Answer 14

When an applied force is multiplied by the distance through which the force is applied

Question 15

Equation for finding work

Answer 15

W=fd

Question 16

Work and energy are measured in

Answer 16

Joules

Question 17

Explain the relationship between work and energy

Answer 17

They’re equal according to the work-energy theorem

Question 18

Equation for finding power

Answer 18

w/t

Question 19

Power

Answer 19

the rate of energy transfer

Question 20

In what unit is work measured in

Answer 20

joules

Question 21

In what unit is power measured in

Answer 21

watts

Question 22

If an area has flowing water and has money to build a dam to connect it to the electricity grid, then they can use this form of renewable energy

Answer 22

Hydroelectric

Question 23

This type of energy is produced when electricity generators are placed on the surface of the ocean. The energy provided is most often used in desalination plants, power planes, and water pumps

Answer 23

Waves

Question 24

This type of energy is created by hot spots; areas where earth’s core heat comes to surface

Answer 24

Hydrothermal and Geothermal

Question 25

This source is often compared compared to batteries; both convert the energy produced by a chemical reaction into usable electric power

Answer 25

Hydrogen Fuel Cells

Question 26

This source of energy is used for powering low voltage devices that are not used often. Its life and endurance is dependent on the apparatus it will energize an the chemical agten involved in its makeup.

Answer 26

Conventional Batteries

Question 27

This type of energy is used throughout areas of the Midwest and in the southern regions of the US and can be a way to generate power to large areas in a fairly inexpensive way.

Answer 27

Wind turbines/generators

Question 28

This source can be made from scraps of plants, grain, wood, and other types of biological material; it converts a solid to a liquid form to use instead of gas in vehicles

Answer 28

Biomass

Question 29

This type of energy relies on steller energy; splitting of heavy atoms and the combining of lighter oens

Answer 29

Nuclear energy

Question 30

Converting landfill hasses into a source of renewable energy is beneficial because it reduced greenhouse gas emissions and can generate revenue from the sale of the electricity

Answer 30

Indirect Natural Gas

Question 31

This type of energy is significant because our society uses large amounts of it and it depends on the use of power plants that convert some other kind of energy into it

Answer 31

Standard Electrical Power

Question 32

This device absorbs light energy from the sun and converts it into usable forms of energy

Answer 32

Solar Cells

Question 33

A bone is like a

Answer 33

lever

Question 34

A muscle contraction is like a

Answer 34

force

Question 35

Joints are like

Answer 35

the fulcrum

Question 36

The resistance is like

Answer 36

the weight of body or lifted object

Question 37

Two inclined planes placed back to back

Answer 37

wedge

Question 38

A circular lever that consists of a grooved wheel rotating about a hub

Answer 38

pulley

Question 39

any slanting surface

Answer 39

inclined plane

Question 40

an inclined plane wrapped around a cylinder

Answer 40

screw

Question 41

A fixed wheel turning on a rod through its center

Answer 41

wheel and axle

Question 42

A rigid bar that rotates on a pivot called a fulcrum

Answer 42

levers

Question 43

First class lever

Answer 43

FUlcrum is in the middle (EFL) seesaw, hammer removing nail

Question 44

Second class lever

Answer 44

the load is in the middle (ELF) paper cutter

Question 45

Third class lever

Answer 45

the effort is in the middle (FEL) rake

Question 46

WHy is gasoline called a "miracle" in the film

Answer 46

can go far with little amount easily refilled, cheap

Question 47

WHat makes electric cars still exesnive

Answer 47

Batteries are expensive

Question 48

What are 2 major advantages of natural gas as an energy source compared to the other fossil fuels

Answer 48

Natural gas is less expensive, environmentally friendly, burns cleaner

Question 49

Do you think nuclear power is a safe form of energy

Answer 49

Yes, it has gotten a lot safer, they're more secure and can withstand drastic weather

Question 50

What does the film say that you and I do to help the global energy demand

Answer 50

Suggest nuclear, natural gas, and renewable energy can be combined to see 50 year crossover

Question 51

Why is the documentary called "Switch?"

Answer 51

They're looking to switch old energy sourced to more environmental and future friendly

Question 52

What are two factors that can influence the price of any type of energy

Answer 52

Supple and demand, natural disasters