Models of the Solar System

Temperature, Heat and the Greenhouse Effect

Thermal Radiation

Efficiency and Sankey Diagrams

Efficiency

·         What two things does efficiency compare?

·         Write down the formula for efficiency.

·         What is efficiency measured in?

·         Can it ever be equal to, or more than 100%? Give a reason for this.

·         Calculate the efficiency of a bulb if Energy in = 100 J and Useful energy out = 10J

·         An equivalent energy saving bulb gives off the same amount of light (100W) but “uses” 25 W of electricity. Calculate its efficiency

·         Calculate the efficiency of a car if Energy in = 5000 J and Energy out = 1250 J