What is the meaning of one watt ?

What is the meaning of one joule ?

(a) What is the meaning of the symbol kWh ? What quantity does it represent ? (b) How much electric energy in kWh is comsumed by an electrical appliance of 1000 watts when it is switched on for 60 minutes ?

Watt is the unit of

A watt is

A watt is

What is the relation between watt and horse power?