Download Unit 2

CH. 2
 Base unit = coulomb
 also the base unit for current and voltage
 Symbol = Q
 Abbreviation = C
 Electric current – movement of charged particles in a
specific direction
 Electrons, pos ions, neg ions
 Speed of light (186,000 miles per sec.)
 Symbol – I (intensity of the electricity)
 Unit of current – ampere (amp)
 Coulombs per second
 1A = 1 coulomb/sec
• Direct current
– Dc
– Current travels in same/one direction
– Flashlight cells, and batteries
• Alternating current
– Ac
– Current periodicallly reverses the direction in which it is
moving
– In your house (every 1/120 of a sec)
– In tv receiver (every 1/67,000,000 of a sec)
 Electric pressure that causes current flow
 Electromotive force (emf)
 Symbol = V
 Types of energy
 Kinetic energy
 Energy in motion, energy doing work, or energy being converted into
another form
 Potential energy
 Energy that can be stored for a long period of time in its present form
 Capable of doing work
 Opposition a material offers to current
 Symbol – R
 Unit of resistance – omega symbol
 Measured in ohms
 Converts electric energy into heat energy when current
is forced through a material