Machine Efficiency

A kettle uses 100J of electrical energy to produce 7J of sound energy and 93J of thermal energy. How efficient is the kettle?

• 100%

• 7%

• 93%

• 95%

Tags

NGSS.MS-PS3-3

A washing machine uses 250J of electrical energy to produce 125J of useful energy. How efficient is it?

• 5%

• 50%

• 55%

• 100%

Tags

NGSS.MS-PS3-4

What type of device might this Sankey be about?

• A very efficient LED light bulb

• A very inefficient incandescent light bulb

• A coal power plant

• A wind turbine

Tags

NGSS.HS-PS3-1

NGSS.HS-PS3-4

No machine in existence has 100% efficiency due to ____________________.

• magic

• friction

• smoke

• input

Tags

NGSS.MS-PS3-5

Which of the following is a measure of a machine's efficiency?

• The amount of energy it consumes

• The ratio of useful work output to total work input

• The speed at which it operates

• The size of the machine

Tags

DOK Level 1: Recall

The percent of energy that is used for work

• Energy efficiency

• Renewable energy

• Nonrenewable energy

• Combustion

Tags

NGSS.MS-PS3-5

the percentage of energy put into a system that does useful work.

• Energy Conservation

• Energy Efficiency

• Energy Wattage

• Electricity

The percentage of energy put into a system that does useful work is:   

• energy conservation

• renewable energy

• energy efficiency

• energy conversion

Tags

NGSS.HS-PS3-3

NGSS.HS-PS3-4

• 100%

• 80%

• 40%

• 10%

Tags

NGSS.MS-PS3-5

the percentage of the input work that is converted to output work

• mechanical advantage

• efficiency

• joule

• machine