Abay : high school physics tutorial

Global top 10 university rank

Simple harmonic motion (SHM) : is a periodic motion in which the acceleration of an oscillator always directly proportional in magnitude but opposite in direction to its displacement .

Grade12 chapter 1
engine is the maximum theoretical efficiency heat engine based on the temperature different between heat source and heat sink.
# the efficiency of diesel engine is greater than petrol engine.

Grade12 chapter 1
# The second law of thermodynamic is also known as the law of impossible .
# it is impossible to make a perfect heat engine with 100% efficiency and a perfect refrigerator with coefficient of performance (cop) infinity .
# it is impossible to flow heat from cold body to hot body spontaneously .
# it is impossible to make a perfect reversible process.

Grade12 chapter1
# Temperature is the measure of the average translation kinetic energy of particles of a substance .

Grade12 chapter 1
# the third law of thermodynamic state that" it is impossible to reach a substance at absolute zero temperature .
zero temperature (0K) is the temperature at which all the energy of the substance become zero and there is no molecular motion at all.

Grade-12 chapter 1
# the entropy of any process in the universe never be decrease .
# for reversible process ,its entropy remains constant .
irreversible process,its entropy always increases .
# any natural processes are irreversible

Grade-12. Ch1
# the first law of thermodynamic is the restatement of the law of conservation of energy as:
Q=U+W

Ethiopian grade-12 physics .ch1: thermodynamics
1.zeroth law of thermodynamic state that 'if body-A and body-B are independenly in thermal equailibrium with body-C then they are in thermal equilibrium with each other.