The quantity of energy converted per unit time which is referred to the power in physics. The watt, which is equal to one joule per second in the International System of Units, is the unit of Power. Power is also referred to the activity in ancient symbol. Power is a scalar quantity.

**What is power class 9?**

We can define Power as the rate at which work is completed, or the amount of work completed in each amount of time. Watt (W), or joules per second (J/s), is the SI unit of Power. Horsepower (hp), which is roughly equal to 745.7 watts, is sometimes used to describe the Power of motor vehicles and other machines.

**Define average power:**

The total energy utilized divided by the total time taken is what we call average power formula. In layman's terms the average power means the average amount of the energy converted per unit of time. To calculate average power, various instruments are employed. When we talk about fiber optic Power instruments, we're talking about devices that measure the average power of a continuous light beam and are used to test signal strength in fiber-optic networks.

W/t=Pav

Note that if the work is done at a constant pace, the average and instantaneous Power are identical, and the common equation is,P=W/t

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**Define si unit of power:**

SI unit of power is watt. The power multiples: KW, MW, GW… One-watt power is achieved when a body performs one joule of work in one second.

1 J/ s Equals 1 watt

horsepower is another unit of power used in British engineering (hp).

1 Horsepower is equal to 746 watts

**Dimension of power:**

P's dimensional formula is M1L2T-3. One Horsepower is defined as 550 foot-pounds per second (746 W) of work performed by a body.

**Device measures power:**

An ammeter is a device that measures the electric current flowing across a circuit. A voltmeter measures the voltage of a device when it is linked in parallel, whereas an ammeter measures the current of a device when it is connected in series. So we can measure resistance as well as power from voltmeter along with ammeter used together. Resistance which is proportional to voltage as well as inversely proportional to current but the power is directly proportional to both voltage as well as current.

Ammeter

**Horsepower**:

The common unit of Power is Horsepower, which refers to the pace at which work is completed. One Horsepower is equal to 33,000 foot-pounds of labor per minute in the British Imperial System, or the Power required to lift a total mass of 33,000 pounds one foot in one minute.

Horsepower

**Electric power formula:**

VI = P

P stands for Power.

V represents the circuit's potential difference, while I is the electric current.

Other Power formulas include:

(This expression is derived from Ohms' law V = IR)

P=I2R=V2R

where R stands for resistance since electrical energy is converted into heat, P=I2R indicates that the larger the electrical current (I), the higher the heat created, and thus the higher the Power/energy loss.

**Power of bulb formula:**

To find power i.e. kilowatt-hour of light bulb which is consumed for a whole month, which we have to multiply by the kilowatt used by the number of hours it's on that particular month.

For example: A light bulb uses 0.05 kW of power and it's consumed for 150 hours a month.

Its Energy usage or Power consumed will be given by (0.05 kW * 150 hours/month) = 7.5 kilowatt-hours per month.

**Some important points regarding power:**

If you want to learn more about our work and energy articles, the following points regarding Power will help you comprehend them better:

- It is the rate of energy consumption.
- It determines how quickly work can be completed.
- Since it is subject to change, there are two approaches to assess Power.
- Instantaneous Power is the Power available at any given time. The average of all the instantaneous Powers is equal to the total energy utilized divided by total time.

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