Physics Unit 5 and 6 Review Flashcards
Motor
Turns electrical energy into mechanical
Generator
Turns mechanical energy into electrical
Step up Transformer
Increases voltage, decreases current
Step down transformer
Decreases voltage, increases current
Purpose of transformer
select applied KV
Four types of transformers and define
Open core-iron cores inserted in coils
Air core-2 coils side by side
Shell-Cinderblock looking iron core and prism/second wrapped around center post of coil
Closed- one continuous loop of core with windings wrapped
What transformer is least efficient
Air
What transformer is most efficient
Shell
Difference between air core and open core
Air core has no core and open core has ferromagnetic core
What are transformers wrapped with to help improve efficiency
laminated silicon steel to hold in power
3 ways to lose power in transformers
Copper-resistance in conductor itself because of diameter and length
Hysteresis: AC fluctuations and realignment of magnetic domain
Eddy: current swirling in the core
Transformers work on what principle
Mutual induction
What current works best with transformers
AC
Transfomer Law
Vp/Vs=Np/Ns
Purpose of Autotransfomers
select the KV
Autotransfomers work on the principle of
Self induction
How do you determine the amount of voltage per tapped turn
dividing total amount of voltage going into by the total turns
auto transformers are also called
Variable ratio transformers
3 phase 6 pulse formula
MAsxKVx1.35
3 phase 12 pulse formula
MAsxKVx1.41
What turns the rotor in an induction motor
rotating magnetic field
Where do you find an induction motor in Xray equipment
target/xray tube
What types of devices are syncronous motors found in
Clocks and timers
What accelerates the electrons from the cathode to the anode
KVP or applied voltage
