Tag: fundamental and derived units

Among the given units watt is the unit of power whereas all others are the units of energy.

Calorie, kilowatt hour, joule all are the units of energy whereas watt is the unit of power.

Power is defined as the work done per unit time. So to get the SI unit of power :

$Power=\dfrac{Work}{Time}$

SI unit of Work $=$ Joules

SI unit of Time $=$ second

So S.I. unit of power $=\dfrac{Joule}{Second}=Watt$

$1000\,Watt=1\,Kilowatt$

The magnitudes of physical quantities can be added together or subtracted from one another only if they have the same dimensions. 

The pascal $(Pa)$ is the SI derived unit of pressure used to quantify internal pressure, stress, Young's modulus and ultimate tensile strength. The unit, named after Blaise Pascal, is defined as one newton per square metre.

We measure the intensity of radioactive emission by  number of atoms that get transformed to new atoms per unit time. 
Curie(Ci) is the standard unit used for measuring radio-activity.
Curie is defined as the emission rate of 1g of radium which is equal to $3.7 \times 10^{10}$ transformations per second.

Electrons spinning on their axes are magnetic dipoles that may or may not cancel out each other depending on the type of dipole.
We measure the  magnetic moment of electron in Joule / Tesla.
The value of magnetic dipole of an electron is $9.27 \times 10^{-24}$ Joule/Tesla.   

The kilowatt-hour ( kWh) is a unit of energy equal to 3600 kilojoules. The kilowatt-hour is a composite unit of energy equal to one kilowatt (kW) of power sustained for one hour.