Examples of watt in the following topics:
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- The unit of power is the joule per second (J/s), known as the watt (in honor of James Watt, the eighteenth-century developer of the steam engine).
- For example, the rate at which a lightbulb transforms electrical energy into heat and light is measured in watts (W)—the more wattage, the more power, or equivalently the more electrical energy is used per unit time .
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- The SI unit for intensity is watts per meter squared or,$\frac W{m^2}$.
- Although the units for sound intensity are technically watts per meter squared, it is much more common for it to be referred to as decibels, dB.
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- Recall that power is the rate at which work is done - or the rate at which energy is consumed or produced - and is measured in watts (W).
- The electric power in watts produced by an electric current I consisting of a charge of Q coulombs every t seconds passing through an electric potential (voltage) difference of V is $P = \frac{QV}{t} = IV$, where Q is electric charge in coulombs, t is time in seconds, I is electric current in amperes, and V is electric potential or voltage in volts.
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- Such graphs are termed indicator diagrams—first used by James Watt and others to monitor the efficiency of engines.
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- where Q/t is the rate of heat transfer in Joules per second (Watts), k is the thermal conductivity of the material, A and d are its surface area and thickness, and (T2−T1) is the temperature difference across the slab.
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- Calculate the heat transfer per unit time in watts needed to warm the incoming cold air by 10.0 ºC, thus replacing the heat transferred by convection alone.