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WATT
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WATT (1240 AM, "News Talk 1240") is a radio station broadcasting a news-talk-sports format. Licensed to Cadillac, Michigan, it began broadcasting in 1946.

Key Information

WATT officially began broadcasting on September 30, 1945, as Cadillac's first radio station[2] on the frequency of 1240 kHz.[3] The station was founded by Les Biederman, a broadcast pioneer who had previously launched WTCM in Traverse City. WATT was a key member of Biederman’s Paul Bunyan Network, a group of small-market stations designed to provide localized news and entertainment to Northern Michigan communities.[4] During its early years, WATT operated with a power of 250 watts and served as an NBC Radio Network affiliate, bringing national programming and block-style variety shows to Wexford County residents.[5]

In the 1970s, Les Biederman sold WATT to Kenneth MacDonald Sr., the founder of MacDonald Broadcasting. MacDonald, a former hall-of-fame broadcaster from Saginaw, purchased the station alongside its FM sister (WLXV) and properties in Petoskey.[6]

In 1998, as part of a corporate reorganization of the family business, the Northern Michigan stations—including WATT—were spun off into a separate entity called MacDonald-Garber Broadcasting, headed by Patricia MacDonald-Garber.[7]

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WATT

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The watt (symbol: W) is the derived unit of power and in the (SI). It is defined as the power that gives rise to energy of one joule in one second. The watt is named in honor of (1736–1819), a Scottish inventor, mechanical engineer, and renowned for his improvements to the , which significantly advanced the efficiency of early industrial machinery and contributed to powering the . Dimensionally, the watt is equivalent to one joule per second (1 W = 1 J/s), or in terms of SI base units, 1 kg⋅m²⋅s⁻³. In electrical systems, it represents the rate of work when a current of one ampere flows under a potential difference of one volt (P = V × I). The unit is widely used to quantify the power consumption or output of electrical devices, engines, and light sources, with common multiples such as the kilowatt (1 kW = 1,000 W) applied to larger scales like household appliances and power plants.

Definition and Fundamentals

Definition

The watt (symbol: W) is the derived unit of power and in the (SI). It is defined as the power that gives rise to of one joule in one second, equivalent to one joule per second (1 W = 1 J/s). Power represents the rate at which work is done or is transferred, and the watt quantifies this rate, with practical measurements often referring to average power over time. In terms of the seven SI base units, the watt is expressed dimensionally as kg⋅m2⋅s−3\mathrm{kg \cdot m^2 \cdot s^{-3}}, where kg denotes (), m denotes (), and s denotes second (time). The unit is named after the Scottish engineer (1736–1819), in recognition of his pioneering work on the .

Mathematical Expression

The power PP delivered by a system is fundamentally defined as the rate at which work WW is done over time tt, expressed as P=WtP = \frac{W}{t}. This formulation arises from the concept that power quantifies how quickly is transferred through mechanical action. Equivalently, power can be described in terms of change, where P=ΔEΔtP = \frac{\Delta E}{\Delta t} and the watt is defined as one joule per second, or 1 W=1 J/s1 \, \mathrm{W} = 1 \, \mathrm{J/s}. This unit reflects the SI standard for power as the rate of transfer. In mechanical contexts, power is given by P=F⋅vP = \mathbf{F} \cdot \mathbf{v}, the product of force F\mathbf{F} and velocity v\mathbf{v}, which follows from substituting work as force times displacement into the time-rate expression and recognizing displacement per time as velocity. The dimensional derivation of the watt from base SI units proceeds as follows: since one joule is 1 J=1 kg⋅m2⋅s−21 \, \mathrm{J} = 1 \, \mathrm{kg \cdot m^2 \cdot s^{-2}}, dividing by time yields 1 W=1 J/s=kg⋅m2⋅s−31 \, \mathrm{W} = 1 \, \mathrm{J/s} = \mathrm{kg \cdot m^2 \cdot s^{-3}}. This confirms the watt's coherence within the SI system, linking mass, length, and time. Instantaneous power represents the power at a specific moment, given by P(t)=dWdtP(t) = \frac{dW}{dt}, the of work with respect to time, whereas power over a period TT is Pavg=1T∫0TP(t) dtP_\mathrm{avg} = \frac{1}{T} \int_0^T P(t) \, dt. This distinction is essential for varying systems, where instantaneous values capture fluctuations and averages provide overall rates.

Historical Development

Origins with James Watt

, a Scottish instrument maker and engineer, significantly advanced technology during the 1760s and 1770s, addressing the inefficiencies of earlier designs like Thomas Newcomen's atmospheric engine. In 1765, while repairing a model at the , Watt conceived the separate condenser, which allowed steam to condense in a separate chamber without cooling the main cylinder, thereby reducing energy loss and reducing fuel consumption by about 75 percent (or increasing efficiency by a factor of about four) compared to prior models. He patented this innovation in 1769, initially partnering with manufacturer John Roebuck, and later refined it through collaborations that introduced planetary gearing for rotary motion by 1781. These developments, patented up to 1782, transformed the from a mere for mines into a versatile power source for mills and factories, fueling Britain's by enabling mechanized production in textiles, mining, and metallurgy. As Watt commercialized his engines in partnership with from 1775 onward, the need arose for a standardized measure of their power output to market them effectively against traditional -drawn machinery. In 1782, Watt proposed the "horsepower" unit, defining it as the work a could perform in lifting 33,000 pounds one foot in one minute (or approximately 550 foot-pounds per second), derived from observations at a Birmingham where horses powered equipment. This metric, slightly inflated from empirical performance data to account for sustained effort, became the basis for rating engines in Britain, with early Boulton & Watt models advertised in multiples of horsepower to demonstrate superiority over animal power. By the , this system was widely adopted in British engineering, facilitating comparisons and sales during the rapid industrialization of the era. Watt's foundational work on power measurement laid the groundwork for the modern unit bearing his name, adopted posthumously in 1889 at the International Electrical Congress in to honor his pioneering quantification of mechanical work. There, the watt was defined as the power equivalent to one joule per second, extending Watt's conceptual legacy from steam to electrical applications while standardizing global engineering practices.

Standardization as SI Unit

The formalization of the watt as a unit within the (SI) began with the 9th General Conference on Weights and Measures (CGPM) in 1948, where the name "watt" (symbol W) was officially adopted for the unit of power, defined as the power corresponding to the production of one joule per second. This decision built on earlier practical electrical units and aimed to standardize nomenclature internationally. The adoption was part of broader efforts to establish coherent units for and , ratified by the 9th CGPM. The SI itself was established by the 11th CGPM in 1960 through Resolution 12, which defined the system as a coherent framework of base and derived units, explicitly including the watt as the derived unit for power (W = J/s). This marked the global adoption of the watt within a unified , promoting its use over disparate national or disciplinary conventions. The International Bureau of Weights and Measures (BIPM), established under the , plays a central role in maintaining and disseminating these definitions, ensuring consistency through ongoing metrological research and international agreements. The transition to the SI facilitated the evolution from earlier systems like the centimetre-gram-second (CGS) framework, where power was expressed in erg per second (1 erg/s = 10^{-7} W), to the more practical metre-kilogram-second (MKS) basis of the SI. This shift, initiated in the early 20th century and finalized in 1960, emphasized coherence—meaning derived units like the watt follow directly from base units without conversion factors—enhancing applicability in science and engineering. A significant update occurred with the 26th CGPM in 2018 (effective 20 May 2019), which redefined the SI base units using fixed values of fundamental constants, including the (h = 6.626 070 15 × 10^{-34} J s). Although the watt's expression (kg m² s^{-3}) remained unchanged, this redefinition indirectly stabilized power units by anchoring the and joule to invariant constants, improving long-term measurement precision without relying on physical artifacts. The BIPM continues to oversee these advancements, supporting the SI's adaptability to new scientific insights.

Units and Scales

SI Prefixes and Submultiples

The (SI) employs a set of standard decimal prefixes to express multiples and submultiples of the watt (W), the unit of power, facilitating the representation of power levels ranging from extremely small to extraordinarily large scales. These prefixes are powers of 10, attached directly to the unit symbol without spaces, such as mW for milliwatt or kW for kilowatt. According to the SI Brochure published by the International Bureau of Weights and Measures (BIPM), prefixes should be used to keep numerical values manageable, avoiding extremes like 101210^{12} or 10−1210^{-12} in favor of TW or , respectively; compound prefixes (e.g., micomilliwatt) are prohibited, and prefixes apply to the base unit without alteration for derived units like the watt. The symbols for prefixes are printed in upright type, with uppercase letters for most multiples (except da, h, k) and lowercase for submultiples. Common SI prefixes applied to the watt include the following:
PrefixSymbolFactorName
milli-m10−310^{-3}milliwatt (mW)
micro-µ10−610^{-6}microwatt (µW)
nano-n10−910^{-9}nanowatt (nW)
kilo-k10310^{3}kilowatt (kW)
mega-M10610^{6}megawatt (MW)
giga-G10910^{9}gigawatt (GW)
tera-T101210^{12}terawatt (TW)
These are among the most frequently used for practical measurements, though the full set extends to yotta- (102410^{24}) and yocto- (10−2410^{-24}). In , the microwatt scale is typical for low-power components, such as sensors in energy-harvesting devices or always-on intelligent sensing systems that operate at around 100 µW. Similarly, terawatts represent peak powers in advanced research, like the 456 TW pulse delivered by lasers at the to achieve conditions. Binary prefixes, such as mebi- (Mi, 2202^{20}), are occasionally referenced in contexts for power scaling in centers or hardware specifications to align with binary storage conventions, but they are not part of the standard SI system and should not be used for general power measurements.

Relation to Other Power Units

The watt, as the SI unit of power, is related to several non-SI units through established conversion factors derived from fundamental physical definitions. In , one mechanical horsepower (hp), defined as the power required to lift 550 pounds by one foot in one second, is exactly equivalent to 745.6998715822702 watts, or approximately 745.7 as per standard tables. Thus, 1 ≈ 0.001341022 hp, providing a direct equivalence for converting between these systems in engineering calculations. Other imperial-derived units include the foot-pound-force per second (ft·lbf/s), a base unit of power in the foot-pound-second system, where 1 ft·lbf/s = 1.355 818 . In the centimeter-gram-second (CGS) system, the erg per second (erg/s) is a smaller unit, with 1 erg/s = 1.0 × 10^{-7} , reflecting the erg's definition as 10^{-7} joules. Historical non-SI units persist in certain contexts, such as the metric horsepower known as cheval-vapeur (CV or ch), originally defined in France as the power to raise 75 kilograms by one meter in one second against gravity (using standard acceleration g = 9.80665 m/s²), equating to exactly 735.49875 W. (Note: Derived from the official definition in the International System context, as confirmed by standard gravitational force calculations.) Despite these equivalences, non-SI units like horsepower continue to be used in the automotive industry, especially for engine ratings in the United States and some markets where PS (Pferdestärke, equivalent to CV) is common in Europe, due to longstanding conventions in marketing and specifications. International bodies, including the National Institute of Standards and Technology (NIST) and the International Bureau of Weights and Measures (BIPM), promote the adoption of the watt and SI prefixes for global consistency, as outlined in SI guides, to facilitate precise scientific and technical communication while allowing limited use of traditional units with conversions.

Applications in Engineering

Electrical Power Measurement

In electrical circuits, the watt quantifies the rate at which is transferred or consumed, serving as the fundamental unit for power measurement in both (DC) and (AC) systems. For DC circuits, where voltage and current are constant, power PP is calculated as the product of voltage VV and current II, given by the P=VIP = V I, with units in watts when VV is in volts and II in amperes. Using (V=IRV = I R), equivalent expressions are P=I2RP = I^2 R and P=V2/RP = V^2 / R, where RR is resistance in ohms; these forms are particularly useful for analyzing resistive loads like heaters or resistors. In AC circuits, power measurement accounts for the phase difference between voltage and current waveforms, distinguishing real power (measured in watts) from apparent power (in volt-amperes, VA). Real power, which performs useful work, is P=VIcos⁡ϕP = V I \cos \phi, where cos⁡ϕ\cos \phi is the power factor representing the cosine of the phase angle ϕ\phi between voltage and current; for purely resistive loads, cos⁡ϕ=1\cos \phi = 1, making real and apparent power equal. Apparent power is simply S=VIS = V I, and the power factor (cos⁡ϕ\cos \phi) typically ranges from 0 to 1 in practical systems, lower values indicating inefficient energy use due to reactive components like inductors or capacitors. This distinction is critical in AC systems, as real power alone determines the actual in watts. Power in electrical systems is measured using specialized instruments such as wattmeters, which compute the average of instantaneous voltage-current products over time to yield true power. Multimeters equipped with watt mode can also derive power by simultaneously measuring voltage and current, though dedicated wattmeters provide higher accuracy for dynamic AC signals. Practical examples illustrate the watt's application: a standard household is rated at 100 , meaning it converts 100 joules of into and per second at typical mains voltage. On a larger scale, electrical power grids transmit in megawatts (MW), with a single often carrying hundreds of MW to distribute power from generators to consumers. In safety contexts, fuse ratings are selected based on the circuit's expected power handling to prevent overheating; for instance, at 230 V, a 3 A fuse accommodates up to approximately 700 without interrupting normal operation, protecting against overloads.

Mechanical and Thermal Power

In mechanical engineering, the watt is commonly used to quantify power in systems involving rotational or linear motion, such as engines and motors. For instance, industrial electric motors are frequently rated in kilowatts, with a typical mid-sized motor delivering 100 kW of mechanical power output under load conditions. This rating represents the rate at which the motor converts electrical energy into mechanical work, often measured as torque multiplied by angular velocity in consistent SI units. Hydraulic systems also employ the to express power transmitted through flow, calculated as the product of differential and : P=Δp QP = \Delta p \, Q where PP is power in , Δp\Delta p is the difference in pascals, and QQ is the flow rate in cubic meters per second. This underscores the 's role in quantifying energy transfer in applications like pumps and actuators, where losses are accounted for separately to derive actual output. In automotive and industrial contexts, dynamometers measure by absorbing while varying speed, generating power curves plotted in kilowatts (or equivalently in horsepower, with 1 hp ≈ 746 ). These tests evaluate peak power and across RPM ranges, aiding for vehicles and machinery. Mechanical power measurements often distinguish between transient and steady-state conditions to capture dynamic behaviors. Steady-state testing assesses sustained output under constant load, while transient analysis examines short-term fluctuations during acceleration or load changes, revealing inertia effects and response times in engines. At the human scale, metabolic power provides a relatable example, with the basal metabolic rate for an average adult approximating 100 W, representing the energy expended at rest to maintain vital functions. In , the watt measures power as the rate of , distinct from mechanical or electrical contexts. Boilers in power plants, for example, are rated in megawatts thermal (MWth), indicating the released per second, such as 500 MWth in a mid-sized unit, which differs from electrical output in megawatts electric (MWe) due to conversion inefficiencies. This notation highlights the watt's versatility in denoting non-electrical flows, like conduction or in heat exchangers, where quantitative assessments focus on steady gradients rather than transient spikes.

Optical and Acoustic Power

In optics, the watt serves as the unit for , representing the total electromagnetic power emitted, transmitted, or received by a light source across all wavelengths. For coherent sources like , output power is directly quantified in watts or fractions thereof; consumer laser pointers, for example, are regulated to a maximum of 5 mW to minimize eye hazards while providing visible beams for pointing applications. This measurement captures the raw without regard to human perception. Photometry adapts the watt for visible light by converting radiant flux to luminous flux in lumens, accounting for the eye's ; the maximum is 683 lm/W at 555 nm, illustrating how 1 W of monochromatic green light equates to 683 lm, whereas broadband sources yield lower efficacy due to varying wavelengths. In medical applications, such as UV sterilization, lamps are rated by electrical input power in watts, with effective UV-C output (e.g., from a 20 W lamp) enabling germicidal effects by inactivating microorganisms on surfaces and in air, as demonstrated in controlled room disinfection studies. Acoustic power, the rate of sound energy emission from a source, is also measured in watts, though practical outputs range from picowatts for faint sounds to watts for loud sources. Speaker ratings typically refer to electrical power handling in watts (e.g., 50–100 for systems), but the resulting acoustic power output is far smaller—often milliwatts at moderate volumes—due to inefficiencies in electroacoustic conversion. Sound power levels are logarithmically scaled in decibels relative to 1 (10^{-12} ), per ISO standards, using the formula LW=10log⁡10(P10−12)L_W = 10 \log_{10} \left( \frac{P}{10^{-12}} \right) dB re 1 , where PP is the sound power in watts; a typical emits about 10^{-6} , or 60 dB re 1 . In radiofrequency contexts, power is often specified in dBm for convenience, convertible to watts via P=10(dBm/10)−3P = 10^{(dBm/10) - 3} ; a common transmitter output of 20 dBm, for instance, corresponds to 0.1 , bridging and measurements. Challenges in these measurements arise from directional emission and environmental interference. Integrating spheres address assessment by enclosing the source in a reflective cavity that averages distribution, enabling precise total determination for lasers and LEDs via detectors at orthogonal ports, unaffected by beam alignment. For acoustics, anechoic chambers simulate free-field conditions by absorbing reflections with wedge-shaped foam, allowing accurate quantification from sources like speakers through and intensity mapping without echo distortion.

Specialized Conventions

Electric Power Industry Practices

In the , is measured in kilowatts (kW) to assess the maximum power required from during a billing period, while average is quantified and billed in kilowatt-hours (kWh) to reflect total usage over time. This distinction allows utilities to charge for capacity to maintain system reliability, with peak kW often determined over 15- to 60-minute intervals within a month, separate from the cumulative kWh that accumulates based on hourly power draw. For example, commercial customers may face charges if their peak exceeds contracted kW limits, incentivizing to avoid penalties. Three-phase power conventions are central to utility transmission and distribution, where the total active power PP in a balanced system is given by P=3 VL IL cos⁡ϕP = \sqrt{3} \, V_L \, I_L \, \cos \phi
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