Power Problems

You do 90 joules of work in 30 seconds. How much power have you generated?

• 30 watts

• 3 watts

• 120 watts

• 270 watts

You move a 0.8 kg object five meters in 4 seconds. How much power have you generated?

• 160 watts

• 10 watts

• 6.4 watts

• 17 watts

Which of the following would produce the most power?

• mass of 10 kilograms lifted 10 meters in 10 seconds 

• mass of 10 kilograms lifted 10 meters in 5 seconds

• mass of 5 kilograms lifted 10 meters in 5 seconds

• mass of 5 kilograms lifted 5 meters in 10 seconds

Tags

NGSS.MS-PS3-4

NGSS.MS-PS3-5

The equation for POWER is

• power = mass x time

• power = work / time

• power = time / work

• power = work x time

A unit of electrical power is the

• a) ohm

• b) volt

• c) watt

• d) amp

What is the power output in Watts of a lightbulb connected in series to a 1.5 V battery if the current flowing through the circuit is 0.5 A? Record your answer. Be sure to use the correct place value.

Mathematical Equivalence

ON

Electrical power can be calculated using

• Resistance x Voltage

• Voltage x Current 

• Voltage ÷ Current

An instrument uses a battery that provides 480 J of energy for 12 seconds. What is the power of the instrument?

Mathematical Equivalence

ON

What is the unit of power in electrical systems?

• Joule

• Watt

• Volt

• Ampere

What is the relationship between Power and Work?

• Power is the rate which Work is done

• Work is not related to Power

• Power is the result of work times the time it takes to complete it