Physics Flashcards
Physics
How much energy is needed to raise the temperature of 500 g of lead by 10 °C? (c = 129 J/kg °C)
645 J of energy is needed. E = mcΔT so 0.5 × 129 × 10 = 645 J.
What is half life
The amount of time it takes for half of the unstable nuclei to decay
What is an isotope
A different version of an atom
Why are isotopes isotopes
Because they have different numbers of neutrons
Latent heat of fusion
The amount of energy needed to melt or freeze a substance
Latent heat of vaporisation
The amount of energy needed to boil it condense a material
Thermal energy changes
∆Et=mxl
Alpha radiation
He -4 -2
Beta radiation
B 0 +1
Gamma radiation
Y 0 0
What happens when you change the internal energy of a substance
It causes it to change temperature or state
What is specific latent heat
The amount of energy needed to change the state of a substance (1kg) without changing temperature
What radiation is the most ionising
Alpha
What radiation is the most penetrating
Gamma
