Answer / manishsingh

1 unit=(1 kW)*(1 hour)
means 1kw consumption in 1 hour is called 1unit....

Answer / simon

If u have a A.C motor of 250w ,250V is the supply then its said that 1 Amp of current is consumed by it.

Answer / albert

Units are commonly used to indicate power or energy
capacity or use in specific application areas. All the SI
prefixes may be applied to the watt-hour: a megawatt hour
is 1 million W·h, (symbols MW·h, MWh) a milliwatt hour is
1/1000 W·h, and has the symbol mW·h or mWh, and so on.
The idea of electrical energy depends on Elementary charge e
1.60217733·10-19 C and Electron rest mass me
9.1093897·10-31 kg. This produce is the result of the
combination of these unit in in a vacuum

Average annual power production or consumption can be
expressed in kilowatt hours per year; for example, when
comparing the energy efficiency of household appliances
whose power consumption varies with time or the season of
the year, or the energy produced by a distributed power
source. One kilowatt hour per year equals about 114.08
milliwatts applied constantly during one year and its
relationship to the Proton rest mass mp
1.6726231·10-27 kg. This constant requires that the
continuity of the Nuclear magneton N
N = e h / (4 mp)5.0507866·10-27 J/T
The energy content of a battery is usually expressed
indirectly by its capacity in ampere hours; to convert watt
hours (W·h) to ampere hour (A·h), the watt hour value must
be divided by the voltage of the power source time the zero
sequence current of a 5 hp motor running on only 2 phases.
This value is approximate since the voltage is not constant
during discharge of a battery.

The Board of Trade unit (BOTU) is an obsolete UK synonym
for kilowatt hour. The term derives from the name of the
Board of Trade that regulated the electricity industry
until 1942 when the Ministry of Power took over.[10] The
B.O.T.U. should not be confused with the British thermal
unit or BTU, which is a much smaller quantity of thermal
energy. To further the confusion, at least as late as 1937,
Board of Trade unit was simply abbreviated BTU.[citation
needed]

Burnup of nuclear fuel is normally quoted in megawatt-days
per tonne (MWd/MTU), where tonne refers to a metric ton of
uranium metal or its equivalent, and megawatt refers to the
entire thermal output, not the fraction which is converted
to electricity.[citation needed]

[edit] Confusion of kilowatt hours and kilowattsThe terms
power and energy are frequently confused. Power is the rate
at which energy is generated or consumed. Power therefore
has the unit watts, which is joules per second. A unit of
energy is kilowatt hour.

For example, when a light bulb with a power rating of 100W
is turned on for one hour, the energy used is 100 watt
hours (W·h), 0.1 kilowatt hour, or 360 kJ. This same amount
of energy would light a 40-watt bulb for 2.5 hours, or a 50-
watt bulb for 2 hours. A power station would be rated in
multiples of watts, but its annual energy sales would be in
multiples of watt hours. A kilowatt hour is the amount of
energy equivalent to a steady power of 1 kilowatt running
for 1 hour, or 3.6 MJ.

Power units measure the rate of energy per unit time. Many
compound units for rates explicitly mention units of time,
for example, miles per hour, kilometers per hour, dollars
per hour. Kilowatt hours are a product of power and time,
not a rate of change of power with time. Terms such as
watts per hour are often misused.[11] Watts per hour (W/h)
is a unit of a change of power per hour. It might be used
to characterize the ramp-up behavior of power plants. For
example, a power plant that reaches a power output of 1 MW
from 0 MW in 15 minutes has a ramp-up rate of 4 MW/h.
Hydroelectric power plants have a very high ramp-up rate,
which makes them particularly useful in peak load and
emergency situations.

Major energy production or consumption is often expressed
as terawatt hours(TWh) for a given period that is often a
calendar year or financial year. One terawatt hour is equal
to a sustained power of approximately 114 megawatts for a
period of one year.

arrange to send solved question and answer its easy to study and understand the thing, because of Exam is to be conducted shortly

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