Question

(a) What is power?
(b) Define $1$ watt of power.
(c) A lamp consumes $1000\,J$ of electrical energy in $10\,s$. What is its power?
(d) Define average power.

Answer 1

Hint: The sum of energy transmitted or transferred per unit time is referred to as power in physics. The watt, which is equivalent to one joule per second in the International System of Units, is the unit of power. Power is often referred to as activity in older books. A scalar quantity is power.

Complete step by step answer:
(a) We may describe power as the rate at which work is completed, or the amount of work completed in a given amount of time. Watt (W), or joules per second (J/s), is the SI unit of electricity. Horsepower (hp), which is roughly equivalent to 745.7 watts, is often used to describe the power of motor vehicles and other devices. Since the Joule is the standard metric unit for function and the second is the standard metric unit for time, the standard metric unit for power is a Joule / second, abbreviated W.

(b) A body is said to have power of $1$ watt if it does work at the rate of $1$ joule in $1\,s$.

(c) $1000\,J$ is the amount of energy absorbed by the lamp.
10 seconds is the time taken
We need to figure out the power of the lamp
\[Power{\text{ }} = {\text{ }}\dfrac{{Work}}{{Time}}\]
$P =\dfrac{W}{t}$
The amount of work done is equal to the amount of energy used by the lamp.
We get the lamp's power by inputting the above values into the power formula.
\[P{\text{ }} = {\text{ }}\frac{{1000}}{{10}}\]
$P = 100\,W$

(d) It's the total amount of work or energy converted in a given amount of time. When the meaning makes it obvious, the average power is also clearly referred to as "power." If the time interval reaches zero, the instantaneous power becomes the limiting value of the average power.

Note:The sum of energy transmitted or transferred per unit time is referred to as power in physics. The watt, which is equivalent to one joule per second in the International System of Units, is the unit of power. Power is often referred to as activity in older books. A scalar quantity is power.