Cette leçon contient 16 diapositives, avec diapositives de texte et 1 vidéo.
Éléments de cette leçon
This lesson
Recap Conservation of energy
Checking the homework
Efficiency and sankey diagrams
Working independently
Slide 1 - Diapositive
Goals
Answering the learning goals of previous lesson
To name the formula for effiency
Applying the formula for effiency
Reading a sankey diagram
Slide 2 - Diapositive
Recap conservation of energy
1. State the law of conservation of energy
2. What is always true about the total amount of energy generated compared to the amount of energy used?
3. What does it mean to say that energy is useful?
What does it mean to say that energy is wasted?
4. What two factors in an energy transfer are compared together to detimerine the efficiency? And how?
Slide 3 - Diapositive
Goals
1. State the law of conservation of energy
2. What is always true about the total amount of energy generated compared to the amount of energy used?
3. What does it mean to say that energy is useful?
What does it mean to say that energy is wasted?
4. What two factors in an energy transfer are compared together to detimerine the efficiency? And how?
Slide 4 - Diapositive
Checking the homework
Exercises §2.5
Slide 5 - Diapositive
Efficiency and
sankey diagrams
Slide 6 - Diapositive
Slide 7 - Vidéo
What is the formula for efficiency?
Slide 8 - Diapositive
Slide 9 - Diapositive
Slide 10 - Diapositive
1) A construction worker puts 20 J of energy in to one strike of his hammer on the head of a nail. The energy transferred to driving the nail in to the wood is 8.0 J. What is the efficiency of the construction worker's hammering?
2) A particular chemical process has an energy efficiency of only 3.00%. To complete this large-scale chemical process, 140,000 J of energy is input. What is the energy output of this process?
