What is one ampere current?

Two long straight thin conductors carrying currents I_1 and I_2 respectively along the same direction are placed parallel to each other in air. Derive an expression for the force per unit length acting on any one of the conductors and hence define one ampere current.

In an n p n transistor circuit, the collector current is 15 mA. If 95% of the electron emitted reach the collector, what is the base current?

A transistor has alpha = 0.95 . If the emitter current is 10 mA , what is the Base current

What is alternating current? Describe.

What is alternating current?

What is the unit of current density?