Scientists use the example of climbing stairs or a ramp to learn about power in physics. The following scenarios provide you with other systems in which you can see power.

Scenario 1: Power in Engines

Engines provide another example of power. The following scenario demonstrates how power relate to car engines.

A 500 hp engine transfers the chemical energy in gasoline into kinetic energy faster than a 300 hp engine, so a car with a 500 hp engine can accelerate from 0 to 20 m/s faster than the same car with a 300 hp engine. Let’s see what that looks like in terms of watts and kilowatts.

A popular car has a horsepower rating of 500. Remember 1 horsepower = 746 watts. How many watts would this be? How many kilowatts?

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Watts - 373,000 w Kilowatts - 373 kw Close Pop Up

Scenario 2: Electrical Systems

a 100 Watt bulb shining brighter than a 60 Watt bulb

Adapted From: Incandescent light bulb, rgesthuizen, Open Clip Art Library

We also see the terms watts and kilowatts (units of power) when talking about electrical systems.

For example, light bulbs come in different wattages. What do you think the difference is between a 100 watt light bulb and a 60 watt light bulb?

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A 100 watt light bulb transfers electrical energy into heat and light faster than a 60 watt light bulb and, therefore, shines brighter.Close Pop Up