transistor current

[amaresh92]

greetings-

suppose a transistor connected with emitter and collector resistor.
when this transistor is given a AC signal, will the current through the emitter and collector resistor will vary as input AC signal varies? variation in AC signal in the sense the direction of flow of current.
thanks

[berkeman]

greetings-

suppose a transistor connected with emitter and collector resistor.
when this transistor is given a AC signal, will the current through the emitter and collector resistor will vary as input AC signal varies? variation in AC signal in the sense the direction of flow of current.
thanks

You are describing the common-emitter configuration of a BJT:

http://en.wikipedia.org/wiki/Common_emitter

And yes, as you vary the base current, that will vary the (amplified) collector & emitter currents. Your base bias does not go negative, however. It varies in positive values to control the collector current.

[sophiecentaur]

greetings-

suppose a transistor connected with emitter and collector resistor.
when this transistor is given a AC signal, will the current through the emitter and collector resistor will vary as input AC signal varies? variation in AC signal in the sense the direction of flow of current.
thanks
I might mention finite current always needs to be flowing Into the base. Its "direction" should not change but its value will vary. Min base current - min collector current : Max base current - max collector current
and emitter current = base current + collector current
Sorry if that's too elementary but I'm not exactly sure what your question means.