To calculate the energy used by a 200 Watt light bulb in one hour, we need to use the formula:
Energy = Power x Time
where Power is the electrical power consumed by the light bulb in Watts, and Time is the duration for which the light bulb was switched on in hours.
In this case, the power consumed by the light bulb is 200 Watts, and the time duration is 1 hour. So, we can substitute these values in the above formula to get:
Energy = 200 Watts x 1 hour
Energy = 200 watt-hours (Wh)
Therefore, a 200 Watt light bulb consumes 200 watt-hours of energy in one hour.