Coco

The formula of electrical work?

• W=UIT

• I=U/R

• P=W/T

• U=IR

Rated voltage means the maxium voltage at whick the electrical meter can be operated safely.

• True

• False

• I don't now

Connect an electric heater to the home circuit seperately, after it has been working normally for 2 hours, the reading of the electric energy meter will change from 4321.8 to4323.4. If the rated voltage of the electric energy heater is 220V, calculate the current passing through the electric heater.

Among the following physical quantities, the unit of which is the name of the scientist "Joule"

• time

• density

• electrical work

• resistance

energy meter can detect

• electrical work

• the intensity of current

• resistance

• power

If R1 < R2, the energy consumed in the same time is W1 and W2 respectively, then

• A.W1＞W2

• B.W1＜W2

• C.W1=W2

• D. It can't be determined

Briefly explain Joule law

The resistance wire in the electric furnace becomes very hot after being enrgized for a period of time, but the wire connected to the electric furnace is not very hot. This is mainly because

• The resistance of the wire is far ;ess than the resistance of the resistance wire, and the wire consumes very little electric energy

• The current through the wire is less than the current through the resistance wire

• Wire radiating is faster than resistance wire

• Wire's insulany is heat insulation

An electricity meter or electrical meter is a device that measure tthe amount of electric energy consumed by a resisdence ,a business, or an electrically powered device.

• True

• False

How to calculate Joule law