Define oxygen and it's uses

Oxygen is a colorless, odorless gas and it is a life supporting component of the air.

It can be used commonly for one of these 3 things:

1. Respiration

2. Metallurgy

3. Rocketry

Hope it helps! : )

the electric field is a “force field” around a charged object that illustrates the direction the electric force would push an imaginary 

need to see circuit to get time constant