what is energy measured in?

Answer 1

http://en.wikipedia.org/wiki/Category:Units_of_energy

Answer 2

Unfortunately, scientists have scrambled to honor their own; so they've coined names for energy in honor of arcane scientists. I find sticking to the SI units of kg-meter-sec suffices in all cases to measure and/or describe energy.

One way to determine proper units of energy is to write out an energy relationship and note the units in that relationship. For example, W = Fd is the so-called work function where F is force and d is the distance the force is applied. Work is just another name for energy; so energy units are force-distance.

Force = ma; so its units are kg-m/sec^2. Thus, force-distance (energy) is (kg-m/sec^2)m = kg (m/sec)^2. So we can work energy problems without ever needing to know that Joules are some arcane term used for energy. Note that kg (m/sec)^2 are also the units for 1/2 mv^2, which is the formula for kinetic energy.

Whether it's for job security or ego build up, the trend to name physical characteristics after little known scientists continues strong. In my life time, for example. we went from a very logical and meaningful cycles/sec to designate frequency to a totally meainingless Hertz for the same thing. Why would anyone want to name a physical characteristic after a car rental? (Just kidding, but get my point.)

Answer 3

different units for different purposes

the scientifically accepted unit is joules.

other units are

kWh for measuring electric energy consumption
eV (electron volt for atomic energy calculations)
erg in cgs system
etc..

Answer 4

depends on the application and the unit system metric you have J or N-m, english you have btu's or ft-lbs

Answer 5

joules or megaelectron volts