P3 Topic 6 (Medical physics) part 1 :)

Medical Physics (Part1): 

• Human energy: - we take in chemical energy in food and drink 
• We use it to move (kinetic energy),make noise(sound energy),gives off heat..

• Joule: -all types of energies are measured in joules(J).It is quite a small unit so (kJ) are commonly used. 1 joule of work = the energy require to move 1 metre against a force of 1 newton. 
• 1 Joule = the same as 1 newton metre(Nm)

• Work :  work is done when there is movement against ; 
• - Any type of friction 
• - The force of gravity 
• - Or when a charged particle is repelled as it moves in an electric field

• Power : the rate of transfer of energy and is measured in watts
• 1 Watt = the same as another unit ,the joule per second (j/s)
• Energy transferred = the same as work done 
• Power = work done…