`P = ( Delta E )/( Delta t )`

Enter a value for all fields

The Power calculator computes the power based on the change in Energy (ΔE) and the time duration (Δt).

INSTRUCTIONS: Choose units and enter the following:

• (ΔE) Change in energy.
• (Δt) Change in time.

Power (P): The calculator returns the power in watts (W).  However, this can be converted to compatible units via the pull-down menu.

The Math / Science

The formula for Power is:

     P = ΔE / ΔT

where:

• P = power
• ΔE = change in energy
• ΔT = change in time

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Power is the amount of energy consumed or produced over time.

• Power is a measurement of the energy used to move vehicles (automobiles, trucks, tractors, trains, boats and airplanes).
• Power is the measurement of energy consumed by a motor and transferred to the drive or wheels. 
• Power is the amount of electrical energy consumed or produced by a system over time such as the energy produced by a hydroelectric dam or energy consumed by an electrical motor.

Power Units

Power is most commonly measured in watts (W).  One watt is equal to one joule per second (1 W = 1 J / 1 s).  Power is also measured in horsepower (hp) where 1 horsepower equals 745.7 watts.  Power is also measured in heat energy transfer as BTUs per hour (BTU/h).

Power Calculators

• Power from Change in Energy over Time
• Power based on Force and Velocity
• P = ΔE / Δt
• ΔE = P * Δt
•  Δt = ΔE / P 
• Power Dissipated by Friction
• Power from Force, Distance and Time
• Power from Resistance and Current
• Power from Voltage and Resistance
• Power from Current and Voltage
• Power textbook chapter (Light and Matter)