Calculating Light Energy and Consumption: A 60W Bulb Left On for 10 Hours

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To calculate the light energy produced by a 60-watt bulb left on for 10 hours with 15% efficiency, first convert the time to seconds, resulting in 36,000 seconds. The total energy consumption is calculated as 60 watts multiplied by 36,000 seconds, equating to 2,160,000 joules. To find the light energy produced, take 15% of this total, which equals 324,000 joules. It's important to note that energy should always be expressed in appropriate units, such as joules. The calculations confirm the energy output and consumption of the bulb.
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hi here is the question

A 60 watt light bulb is left swithed on for 10 hours. If the light bulb is 15% effcient, calculate the amount of light energy produced in that time. what is the total energy consumption of the light bulb in this time.

so i need to find work done right so is that power divided by time to get the energy and then find 15% of that am i right i am bathed by this.
 
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A watt is 1 unit of energy per unit time. You know how much of the energy was turned into light (15%) and the length of time the light was left on. No need to introduce work.
 
so do i divide watts by time taken?
 
so 60 watts divided by10 hours which is 6 15% of 6 is 0.9 if i am correct

can you please tell me if i am right if not can you advive me where i went wrong
 
your answer is incorrect. First you need to think about units
watts is per second whereas you're given a time in hours. Secondly do you think the energy would be lower or higher than how much you are using in one second?
 
so 10 hours is 600 minutes 36000 seconds and 60 watts goes goes in in 36000 2160000 so 15% 324000 am i right
 
Correct. now remember to state you units. energy is measured in...
 
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