Get reliable answers to your questions at Westonci.ca, where our knowledgeable community is always ready to help. Get quick and reliable solutions to your questions from a community of experienced professionals on our platform. Get precise and detailed answers to your questions from a knowledgeable community of experts on our Q&A platform.

Many of the houses have fireplaces that are
15 percent efficient and use 15 kg of wood to
heat a room to 20°C (68°F). Wanting to reduce
their ecological footprint, several of the home-
owners are considering switching to woodstoves
that are 75 percent efficient. If they do change to
using a woodstove, how many kilograms of wood


Sagot :

By using a woodstove, the kilograms of wood required to

heat a room to 20°C is 3 kg

Efficiency of a machine

  • Efficiency is the percent of work put into a machine (input work) to that of the work done by the machine (output work).
  • Efficiency of a machine is always less than 100% because the output work is always less than the input work because some of the input work is used to overcome friction.

Efficiency = work output/work input * 100%

Efficiency of fireplaces = 15%

Amount of food required to heat a room to 20°C = 15 kg

Assuming efficiency of 100%, amount of wood required will be X kg:

X = 15% * 15 kg

X = 2.25 Kg

By switching to woodstoves which are 75% efficient, amount of wood required will be Y kg:

Y = 2.25 kg / 75%

Y = 3 kg

Therefore, by using a woodstove, the kilograms of wood required to

heat a room to 20°C is 3 kg

Learn more about efficiency of machines at: https://brainly.com/question/3617034

We hope you found what you were looking for. Feel free to revisit us for more answers and updated information. Thank you for choosing our platform. We're dedicated to providing the best answers for all your questions. Visit us again. Get the answers you need at Westonci.ca. Stay informed with our latest expert advice.