Alightbulb has a power of 100 w and is used for 4 hours. a microwave has a power of 1200 w and is used for 5 minutes. how much energy is used by the lightbulb? how much energy is used by the microwave? the lightbulb has an efficiency of 1.8%. how much heat energy does the lightbulb produce in 4 hours?

a. E=1440KJ

b. E=360KJ

c. E=1.8 J

Explanation:

I have the power (Watts) is expressed as Energy (Joules) / Time (seconds), also I have to

so, for the lightbulb

Analogously, for the microwave

Now, I have to express the efficiency as Heat energy / power * 100 so

Done

if i am correct, your answer choices are:

a. the temperature remains constant

b. the temperature increases at a constant rate

c. heat flows at a constant rate into the system

d. heat flows at a constant rate out of the system

e. no heat flows into or out of the system

if so, then the answer is e. no heat flows into or out of the system.