Welcome Back

Sign in to your PART66Online account

or use email
Forgot password?

Don't have an account? Register here

Module 3. Electrical fundamentals

A near perfect 4:1 step up transformer has it`s primary connected to 120VAC, if the secondary is connected to a load with 1600 ohms resistance, what is the current in the primary?

  • 0.3 amps.
  • 1 amp.
  • 1.2 amps.

Explanation

The 4:1 step-up raises 120 V to 480 V on the secondary, so the secondary current is 480/1600 = 0.3 A and the load power is 480 x 0.3 = 144 W. In a near-perfect transformer the primary power matches, so the primary current is 144 W / 120 V = 1.2 A. Equivalently, primary current is four times the 0.3 A secondary current.

wenyang asking:

Why

Community Comments (0)

No one has posted a comment here yet.

Please Sign In to post a comment.

We use essential cookies to keep you signed in, plus anonymous analytics to understand how the site is used. Cookie-based analytics is set only with your consent. See our Privacy & Cookie Policy.