Define power in energy terms.

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Multiple Choice

Define power in energy terms.

Power is how fast energy is transferred or used. It measures the rate at which energy flows, so the bigger the power, the quicker energy is being moved or converted. Since energy is measured in joules and time in seconds, the unit is watts (one joule per second). The idea is captured by P = E/t: if you move E joules in t seconds, the power is E divided by t. For example, a 100-watt light bulb uses about 100 joules of energy every second. The energy stored in an object describes how much energy it has, not how quickly that energy is being transferred. The rate of change of momentum relates to force and motion, not energy transfer rate. Energy per distance would be energy per length, not energy per time, so it doesn’t define power.

Power is how fast energy is transferred or used. It measures the rate at which energy flows, so the bigger the power, the quicker energy is being moved or converted. Since energy is measured in joules and time in seconds, the unit is watts (one joule per second). The idea is captured by P = E/t: if you move E joules in t seconds, the power is E divided by t. For example, a 100-watt light bulb uses about 100 joules of energy every second.

The energy stored in an object describes how much energy it has, not how quickly that energy is being transferred. The rate of change of momentum relates to force and motion, not energy transfer rate. Energy per distance would be energy per length, not energy per time, so it doesn’t define power.

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