Engine problems and protecting nature
Answers are for parents and teachers.
1
An engine does 800 J of work and gives 2400 J to the cooler. Find Q₁ and η.
Q₁ = 3200 J, η = 25 %
2
η = 40 %, A = 6 kJ. Heat given to the cooler (kJ)?
9
3
T₁ = 900 K, T₂ = 300 K. Efficiency of the ideal engine (%)?
67 % (approximately)
4
Write two concrete ways to reduce air pollution in your town or village.
For example, use public transport and plant trees.
5
Why does an engine efficiency below 100 % lead to thermal pollution?
Part of the fuel’s energy is given to the cooler, i.e. to the surroundings as heat, warming the environment.