Understanding Power in Physics

What is one of the most common definitions of power in physics?

• The amount of energy stored in an object

• The rate at which work is done

• The total work done over a lifetime

• The speed of an object

Which unit is used to measure power?

• Newton

• Joule

• Pascal

• Watt

If a light bulb converts 2000 joules of energy in 300 seconds, what is its power rating?

• 6.67 watts

• 10 watts

• 8 watts

• 5 watts

A jogger exerts 2500 watts of power for 9.5 seconds. How much work does she do?

• 20,000 joules

• 25,000 joules

• 23,750 joules

• 22,500 joules

What is the power output of a crane that does 450,000 joules of work in 3 seconds?

• 50,000 watts

• 100,000 watts

• 200,000 watts

• 150,000 watts

How much force does a crane need to lift a 7500 kg container at a constant velocity?

• 80,000 newtons

• 70,000 newtons

• 75,000 newtons

• 73,575 newtons

What is the work done by a crane lifting a container 6.5 meters high?

• 470,000 joules

• 450,000 joules

• 480,000 joules

• 460,000 joules

How much power does a person exert when running up stairs if they do 3510 joules of work in 2.25 seconds?

• 1500 watts

• 1600 watts

• 1300 watts

• 1400 watts

What is the weight of a person with a mass of 55 kg?

• 540 newtons

• 550 newtons

• 560 newtons

• 530 newtons

If a person runs up a flight of stairs in 2.25 seconds, what is the vertical height they cover if they exert 3510 joules of work?

• 6.5 meters

• 7 meters

• 5.5 meters

• 6 meters