A '100-W' lamp consumes energy at the rate of 100 joules per second.
One unit of electrical energy is a kilowatt hour (1kWh). If you leave the bulb on for ten hours, it will use 1 unit of energy. A 60 watt bulb would take 16 hours 40 minutes to use the same single unit of energy.
Answer
Power may be defined as 'the rate at which energy is consumed'. It is measured in watts which, under SI, is a special name given to a joule per second.
So, if a lamp is rated at 100 W, then it consumes 100 joules of energy per hour. As a joule is a relatively small unit of measurement, energy supply companies measure energy consumption in a much larger unit, called the 'kilowatt hour' (note, NOT a kilowatt per hour!). In the UK, the kilowatt hour is frequently referred to as an 'unit' which is short for 'Board of Trade Unit' (a government organisation that used to control the cost of energy, now defunct).
A kilowatt hour, or unit, is defined as 'the energy consumed, per hour, at the rate of one kilowatt'.
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The rating indicates the amount of power consumed by the light bulb. In this case, a 100-watt light bulb consumes 100 watts of electricity when it is turned on.
The watt is the SI unit for power and measures the rate at which energy is consumed by an appliance. It's a special name given to a joule per second.
It is the rated load that is applied to the circuit that the bulb is in. In laymen's terms, it is bulb brightness. The higher the wattage the brighter the bulb will glow.
The power rating of a light bulb is measured in watts (W), which represents the amount of electrical energy it consumes per unit of time. If a light bulb has a power rating of 60 watts (for example), it means it consumes 60 watt-hours of energy in one hour of operation.
A light bulb is typically measured in watts, which indicates its power consumption and brightness output. It can also be measured in lumens, which quantifies the amount of light produced by the bulb.
A typical recessed light can use anywhere from 7 to 100 watts, depending on the type of bulb used (LED, incandescent, or halogen) and the brightness desired. LED lights are more energy-efficient, using fewer watts compared to incandescent or halogen bulbs.
A 921 bulb refers to a specific type of automotive light bulb commonly used in car interiors, RVs, and boats. The "921" designation indicates the bulb's size and base type, which in this case is a wedge base with a T5 shape. It typically emits a bright, white light and is known for its energy efficiency and long lifespan.
The power of a light bulb is typically measured in watts and indicates how much energy the bulb consumes. A higher wattage bulb will produce more light but also consume more energy. LED bulbs are more energy-efficient and have lower power consumption compared to traditional incandescent bulbs.