Power Formula Physics Voltage

Power current and voltage calculations for gcse physics.

Power formula physics voltage. If there is ac look also at the power factor pf cos φ and φ power factor angle phase angle between voltage and amperage. Power is measured in units of watts w where a watt is equal to a joule per second 1 w 1 j s. Electric power is the rate per unit time at which electrical energy is transferred by an electric circuit the si unit of power is the watt one joule per second. Power p i v r i 2 v 2 r where power p is in watts voltage v is in volts and current i is in amperes dc.

In older works power is sometimes called activity. For any circuit element the power is equal to the voltage difference across the element multiplied by the current. So power energy time. In physics power is the amount of energy transferred or converted per unit time.

Power current and voltage calculations for gcse physics. Power formula 1 electrical power equation. Electric power is a widely used term in physics as you must be aware of. The standard metric unit of power is the watt.

Power p is the rate of energy transfer it is measured in watts w where one watt is defined as one joule per second hence watts can be expressed in base units as kgm 2 s 3. This formula can be used to substitute for the voltage or for the current in the power formula and. The output power of a motor is the product of the torque that the motor generates and the angular velocity of its output shaft. The above equation can be rearranged to give i p v and v p i on the next page we shall see how to calculate the power.

By ohm s law v ir and so there are additional forms of the electric power formula for resistors. Power is a scalar quantity. In the international system of units the unit of power is the watt equal to one joule per second. An electric machine makes use of 300 j of energy to do work in 10s.

Electric power is usually produced by electric generators but can also be supplied by sources such as electric batteries it is usually supplied to businesses and homes as domestic mains electricity by the electric power industry. P e t. Voltage is the energy e per charge q voltage is measured in volts v which is defined as one joule per coulomb voltage can be defined in base units as kgm 2 s 3 a 1. Moreover it is a very important thing that allows us to see the rate at which electrical energy transfers from an electric circuit.

5 1 customer reviews. Since 1 volt 1 joule per coulomb and 1 amp 1 coulomb per second. The power formula is used to compute the power resistance voltage or current in any electrical circuit. P v x i.

Work done w 300 j time taken t 10 s. Similarly you will learn about the electric power formula in detail over here. This equation is important. Then watts volts x amps or power voltage x current.