Chemistry 131 NEED HELP PLEASE

Question

An office heater puts out  (British thermal units) of energy in the form of heat per hour. Given that  how many megajoules of energy in the form of heat can be produced per year (365 days) by the heater, assuming continuous operation?

Answer 1

First we need the conversion factor between BTU, British Thermal Unit, and MJ, megajoules. Textbooks will have this conversion factor as follows:

1 BTU = 0.0011 MJ

Now we need to find out how many hours are in a year. To do this, we use dimensional analysis:

1 year (365 days/1 year) ( 24 hours/ 1 day) = 8760 hours.

Actual numbers were not given, but to demonstrate how to work this problem, I am going to assume an office heater puts out 100 BTU per hour.

100 BTU/hour ( 0.0011 MJ/BTU) (8760 hours) = 963.6 MJ

There will be 936.6 MJ per hour.