sci- energy Flashcards
how do energy transfers work
energy transfer occurs when the energy is transferred to another object
what is the energy transfer equation
energy in——> energy out
what is energy measured in
Joules (J) or kilojoules (kJ)
what is the conservation of energy
energy can be changed from one form to another, but it is never created and never destroyed. Energy can either be transformed between one type to another or transferred to another object
what is active energy
detected when particles, waves or objects move
what is potential energy
energy which is stored and cannot be detected until it is transformed into active energy
what are some types of active energy
heat, light, sound, kinetic, electromagnetic
what are some types of potential energy
chemical, gravitational, magnetic, nuclear, mechanical, elastic
how do u work out effeciency
effeciency= useful energy/ input energy x100
what does gpe=
mgh or mxgxh
what is efficiency
how much useful energy you get out of a process compared to how much you put into it
where does our food get its energy from
photosynthesis/ sunlight
where do we get our energy from
food
how do we calculate how much energy our food has
Q= m c 🔼T
Q= energy given out by burning food J
m= mass of water heated by burning food g
c= specific heat capacity of water (4.2)
🔼T= change in temperature of water
how do we calculate how much energy our food has equation
energy released from food per gram (J)= mass of water (g) x temp rise x 4.2/ mass of food sample (g)
