If an appliance has a power rating of 2,000 watts and it is switched on for 2 hours, you can calculate the total energy consumed using the formula:
Energy (in watt-hours) = Power (in watts) x Time (in hours)
Plugging in the values:
Energy = 2,000 watts x 2 hours = 4,000 watt-hours
Therefore, the appliance will consume 4,000 watt-hours of energy.