Ben wants to know how much energy his common household appliances are using each day (24 hours). He uses his 1200 W microwave for 20 minutes a day. He has his single 100 W lightbulb on for 6 hours a day. He runs his 400,000 W death laser for 5 seconds a day. Which item uses the most energy per day? A. The microwave. B. The lightbulb. C. The death laser. D. They all use the same amount of energy. E. They create power but do not use any energy<\/p>\n\n\n\n
The correct answer and explanation is:<\/strong><\/mark><\/p>\n\n\n\n The correct answer is B. The lightbulb<\/strong>.<\/p>\n\n\n\n Here’s why:<\/p>\n\n\n\n Energy usage is calculated by multiplying power by time. Power is measured in watts (W), and time should be in hours (h) for energy in watt-hours (Wh).<\/p>\n\n\n\n Let’s calculate the daily energy consumption for each appliance:<\/p>\n\n\n\n Comparing these:<\/p>\n\n\n\n The lightbulb uses the most energy in a day, even though its power rating is much lower than the death laser’s, because it is on for a much longer time (6 hours vs. 5 seconds).<\/p>\n\n\n\n This example shows that energy consumption depends on both the power of the device and how long it is used. A high-power device used briefly may consume less energy than a low-power device used for many hours. Energy is what costs money and affects electricity bills, while power is just the rate of using energy.<\/p>\n\n\n\n Option E is incorrect because all these appliances consume energy to operate. Option D is incorrect because the energy usage differs. Therefore, the best answer is B. The lightbulb<\/strong>.<\/p>\n","protected":false},"excerpt":{"rendered":" Ben wants to know how much energy his common household appliances are using each day (24 hours). He uses his 1200 W microwave for 20 minutes a day. He has his single 100 W lightbulb on for 6 hours a day. He runs his 400,000 W death laser for 5 seconds a day. Which item […]<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[1],"tags":[],"class_list":["post-31211","post","type-post","status-publish","format-standard","hentry","category-quiz-questions"],"_links":{"self":[{"href":"https:\/\/gaviki.com\/blog\/wp-json\/wp\/v2\/posts\/31211","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/gaviki.com\/blog\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/gaviki.com\/blog\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/gaviki.com\/blog\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/gaviki.com\/blog\/wp-json\/wp\/v2\/comments?post=31211"}],"version-history":[{"count":1,"href":"https:\/\/gaviki.com\/blog\/wp-json\/wp\/v2\/posts\/31211\/revisions"}],"predecessor-version":[{"id":31212,"href":"https:\/\/gaviki.com\/blog\/wp-json\/wp\/v2\/posts\/31211\/revisions\/31212"}],"wp:attachment":[{"href":"https:\/\/gaviki.com\/blog\/wp-json\/wp\/v2\/media?parent=31211"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/gaviki.com\/blog\/wp-json\/wp\/v2\/categories?post=31211"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/gaviki.com\/blog\/wp-json\/wp\/v2\/tags?post=31211"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}\n
Power = 1200 W
Time = 20 minutes = 20 \u00f7 60 = 0.333 hours
Energy = Power \u00d7 Time = 1200 W \u00d7 0.333 h = 400 Wh<\/li>\n\n\n\n
Power = 100 W
Time = 6 hours
Energy = 100 W \u00d7 6 h = 600 Wh<\/li>\n\n\n\n
Power = 400,000 W (400 kW)
Time = 5 seconds = 5 \u00f7 3600 = 0.00139 hours
Energy = 400,000 W \u00d7 0.00139 h \u2248 555.6 Wh<\/li>\n<\/ol>\n\n\n\n\n